So who knew it would get this hot today? It's 87 degrees at Calvert & Centre at 2 p.m., with a couple more hours of solar heating ahead of us. It's 83 degrees out at BWI. That's already 14 degrees above the normal high for an April 30 at the airport. The record for the date is 92 degrees, set in 1910.

The heat cranked up after that little disturbance swept through with some sprinkles this morning. Skies cleared quickly after that and temps shot up - from 61 degrees at 7 a.m. to 79 down here in Newspaper Gulch just four hours later.

The two Washington airports are both reporting 85 degrees and sunny. And I'm stuck here in the newsroom, where it's a steady 75. And gray. Dang.

Posted by Frank Roylance at 1:58 PM | Permalink | Comments (0)
Categories: Events
        

May arrives tomorrow with the promise of a spectacular week. OK, so there may be a bit of a thunderstorm overnight Tuesday into Wednesday. But you'll be home in bed, and only the flowers and the new grass will be out there to deal with it.

The rest of the week promises to be sun-blessed and mild, with daytime highs in the upper 60s and 70s. No charge. Just enjoy.

In the weather records, May in Baltimore comes with average daytime highs rising through the 70s, from 69 degrees in May Day, to 79 degrees by month's end. The average lows at BWI run from 47 degrees on the 1st to 57 degrees on the 31st.

We all know the weather can, and probably will bring more impressive extremes. The record highs are all in the 90s, with the exception of May 1 (89 degrees) and May 2 (88). The hottest May days on record for Baltimore reached 98 degrees, on May 19, 1962 and again on May 30, 1991.

Record cold for May was the 32-degree day that occurred on May 11, 1966. Snow can fall in May. But the only record of it are the traces that fell on May 1, 1963 and on May 9, 1923 - the latest snowfall on record for Baltimore.

May's arrival, of course, means that April 2007 slips into the record books. It was a cool one, but moderating weather late in the month saved us from setting a new record for cold April. 

We still have to add today's average to the calculation. But it appears this month will end with an average temperature of around 50.9 degrees. That would make this the 7th coolest on record since the official weather station moved to BWI in 1950. The last April to end up cooler than that was 25 years ago, in 1982, when we clocked an average of 50.7 degrees. The coolest April in that period averaged 49.5 degrees, in 1966.

The low average temperature can be laid to the persistently cold weather we saw early in April. We had a solid week - from the 5th to the 11th - with average daily temperatures 10 degrees or more below the long-term averages. The month's low was a 26-degree morning on the 9th. Things didn't really warm up until the third week in April, with a string of days in the 80s. before the recent cool-off. The month's high temperature was 85 degrees, on the 23rd.

Rainfall during April totaled an even 5 inches. That was more than 2 inches above the long-term average. You can atrribute all of it to the soaking we received on the 14th and 15th, when 2.74 inches fell at BWI.

Posted by Frank Roylance at 10:45 AM | Permalink | Comments (0)
Categories: Forecasts
        

Got the afternoon off Wednesday?  Why not drive out to Martin State Aiport and see the National Oceanic and Atmospheric Administration's "Hurricane Hunter" aircraft? The Orion WP3 will be visiting as part of NOAA's effort to call attention to its role in forecasting the track and power of hurricanes as they approach the U.S. coastline.

The airplane will be open to visitors, and local and state emergency services personnel will have displays on site, too. Here's the lowdown from NOAA. And here's more on NOAA's Hurricane Hunter squadron. They're part of the nation's smallest uniformed service, the NOAA Commissioned Corps., based at MacDill Air Force Base, in Tampa. Here are some of their coolest weather photos.

The NOAA Hurricane Hunters are distinct from the Hurricane Hunters of the 53rd Weather Reconaissance Squadron, part of the Air Force Reserve, based at Keesler AFB, in Biloxi, Miss.

Posted by Frank Roylance at 1:11 PM | Permalink | Comments (0)
Categories: Hurricane background
        

Warm front, cold front, rain, wind and maybe a thunderstorm. It all adds up to a rocky day of transition weather on tap today. Here's the official forecast. It's dark and dank, but you can see the light at the end of today's tunnel. Look for the cold front to pass through by the end of the day. Here's the weather map showing the front as a north-south blue line, headed east. A nice weekend ahead.

UPDATE: Is this really necessary? Most of the "rocky" weather this afternoon passed well to our south and east. This morning's went north. We appear to be in the clear. Have a nice weekend. 

EARLIER: We seem to have missed the intense rainfall that's occurred to our north and east, especially in flood-weary New Jersey. Here's the Northeast radar loop. But there's more ahead. Here's a part of this morning's discussion out at NWS Sterling:

SCATTERED THUNDERSTORMS WILL AFFECT THE REGION TODAY. AS A WARM
FRONT LIFTS NORTH FROM SOUTHERN VIRGINIA...PORTIONS OF NORTH
CENTRAL VIRGINIA AND LOWER SOUTHERN MARYLAND WILL LIKELY WARM
THROUGH THE 70S WITH PARTIAL SUNSHINE. A FEW OF THE THUNDERSTORMS
ALONG AND SOUTHEAST OF INTERSTATE 95 WILL HAVE THE POTENTIAL FOR LARGE
HAIL...LOCAL DAMAGING WIND GUSTS AND AN ISOLATED TORNADO THIS
AFTERNOON AND EARLY EVENING. THE THREAT FOR SEVERE WEATHER WILL
WANE WITH THE PASSAGE OF A COLD FRONT FROM THE WEST DURING THE
EVENING HOURS.

The rain has been raising streamflows in parts of central Maryland, mostly to the north and west of Baltimore. You can keep tabs on them here.

Posted by Frank Roylance at 7:49 AM | Permalink | Comments (0)
Categories: Forecasts
        

There's a powerful storm center in the neighborhood, and an associated cold front is approaching from the west. Forecasters expect it to sweep through our area Friday, bringing wind and rain, and a chance for a severe storm, complete with thunder, lightning and hail, along the I-95 corridor. 

Here's the official forecast. And here's how AccuWeather sees it. And here's the weather map. That blue line snaking down the spine of the Appalachians in the cold front, headed our way.

The ironic thing about this front is that it will usher in not cold weather, but a warmup, as sunshine returns and the wind shifts from off the Atlantic (source of the east winds and cool damp weather we're feeling now), to the south. That will pop the temps back up into the 70s for the weekend. 

That will come too late for tonight's flyover by the International Space Station. It would have been a nice one, right over Baltimore. In case you get a break in the clouds, you can look for the ISS to rise above the Northwest horizon at 8:33 p.m. and fly almost exactly over the city, reaching a high point of 80 degrees above the Northeast horizon at 8:36 p.m. From there it will move off toward the Southeast, disappearing at about 8:38 p.m.

Look for a white, star-like object moving at a fine clip (17,500 mph) across the sky. If it blinks or sports colored lights, it's an airplane, not the ISS, which only reflects sunlight. But as I said, clouds are likely to obscure the view.

Posted by Frank Roylance at 2:20 PM | Permalink | Comments (0)
Categories: Forecasts
        

Astronomers say temperatures on their newly-discovered planet Gliese 581c are within the range in which water would be liquid. It's circling an unremarkable red dwarf star called Gliese 581, and close enough so that even the star's relatively weak light would be enough to keep the planet mild - in the star's "habitable zone."

No evidence available yet to determine whether anything's breathing in Gliese 581c. But you can bet scientists will be doing everything they can think of to tease any hint of life from any candidate planet they find. Anyway, here's what Gliese 581 - the star - looks like from here. Pretty nondescript. I would imagine we look almost as obscure to anyone - or anything - looking back at us. Here's what the place might look like. Here's an artist's view from the surface. Very cool.

For their sake, I hope it's warmer and sunnier there today than it is here. It's 54 degrees at Calvert & Centre this morning, barely a degree warmer than the overnight low. Gray skies and cool weather will continue. Our forecast high today is only 58, quite a comedown from the 80-degree weather we were enjoying earlier in the week.

Look for rain later today, tonight and tomorrow as the next cold front stomps through. We can use it. Hasn't rained in any measurable amounts in 10 days. Here's the official forecast from Sterling. We'll live for the weekend - sunny and 70s.

Posted by Frank Roylance at 10:03 AM | Permalink | Comments (0)
Categories: Cool pictures
        

The Chinese are worried about dirty, polluted air in Beijing during the 2008 Summer Olympics. But, they have a plan. Rather than actually cleaning up the sources of their worst-in-the-world air pollution, they plan to fire rockets into the sky, release silver iodide crystals, and wait for the resulting rain to cleanse the air. Read more here.

Never mind that the scientific evidence for such "weather modification" has been described by most of the world's scientists as inconclusive at best. The Chinese invented rockets, and by Golly they're going to use them.

It reminds me of my days writing for the New Bedford (Mass.) Standard Times. I was assigned to find the most obscure, oddball state agencies still on the books, but with little or nothing to do, and write about them.

One was the state's 1950s-era "Weather Modification Office." It was the job of the bureaucrats in that office to examine and approve (or disapprove) proposals by entrepreneurs to "seed" clouds for farmers and communities troubled by drought or otherwise eager for rain.

Sometimes it rained, and sometimes it didn't. Of, course, that would have been true even if they hadn't taken to the skies to drop silver iodide into the most promising clouds they could find. They went about their business, crowed about their "successes" and collected their dough. Eventually, people recognized they weren't getting much in the way of results. 

Curiously, although the data demonstrating that it works are still not in, the industry has not gone away. And weather modification remains a tantalizing possibility for entrepreneurs and scientists and public officials in dry regions. Here is a sane discussion of where things stand in Arizona. 

Posted by Frank Roylance at 3:22 PM | Permalink | Comments (0)
Categories: History
        

The official forecast from Sterling made it look like mid-week would be gray and rainy. A weak cool front from the north was to push through, lower temperatures, cloud up the sky and bring showers.

Well, the front moved through alright. The temperature here at Calvert & Centre dropped from 84 degrees yesterday afternoon to 60 degrees by sunrise today. And we've only crept up to 69 degrees so far this afternoon.

But the morning remained very sunny. If you left your car closed up, it was July-hot by the time you returned this morning, thanks to the solar heating.

Forecasters insist there's rain on the way. The cool front, which slid to our south overnight, will be creeping north again as a warm front this time. THAT should bring us some showers. And then we'll begin to feel the effects of a real cold front approaching from the west - the same one that's been causing a lot of violent weather to our southwest. Here's AccuWeather's take on it.

The good news is it should all move through by Friday, leaving the door open for a fine weekend.

Posted by Frank Roylance at 1:12 PM | Permalink | Comments (0)
Categories: Forecasts
        

As a cool front inches down on us from central Pennsylvania today, the sun will be less and less in evidence. We could even see some showers or thundershowers. But the sun is still up there somewhere, and thanks to NASA's STEREO mission we can now see it in 3-D.

Here's a photograph of the sun as it appears in ultraviolet light, which captures emissions from the hottest regions of the sun's upper atmosphere, or corona - more than 2 million degrees. You'll need red-and-cyan (blue) 3-D glasses to get the threee-dimensional effect. So dig deep into the family junk drawer, find those old 3-D glasses and have a look.

You can find even more 3-D images of the sun at NASA's STEREO site. And you can read today's story in The Sun. Just click here.

Posted by Frank Roylance at 10:31 AM | Permalink | Comments (0)
Categories: Cool pictures
        

All this sweet, sunny, spring weather is going to disappear for the rest of the week. The high-pressure system that brought us the mild flow of air from the south and the clear, sunny, starry skies, is moving away, replaced by a weak cool front that's expected to stall just to our south. That will put us in line for cooler weather and an increasing chances for showers, thunderstorms and rain as the week moves along, and a stronger storm system moves through by Friday. Here's the official forecast from Sterling.

After that we can look forward to a better weekend, with some sunshine and comfortable temperatures.

In the meantime, we reached a summerlike 87 degrees today here at Calvert & Centre streets. It was 85 degrees at 4 p.m. at BWI, the official weather station for the city. That was toasty, but well short of the record for the date. That was 94 degrees, reached on this date in 1960.

Posted by Frank Roylance at 6:08 PM | Permalink | Comments (0)
Categories: Forecasts
        

The mercury out at BWI reached 77 degrees yesterday, the warmest since our April weather began to deteriorate after an 80-degree day on the 2nd. We should easily top that high mark today and tomorrow. The forecasters out at Sterling say we'll reach 82 or 83 today and tomorrow as we continue to enjoy strong sunshine beneath a large high-pressure system that has slid across the eastern U.S. 

Stations farther inland, away from the bay, saw readings in the 80s yesterday.

But the fine weather begins to give way late Monday, and we'll face a small threat of showers for the rest of the week as week storms and finally a cold front approach from the north and west. Here's AccuWeather's take on the impending change.

Posted by Frank Roylance at 9:38 AM | Permalink | Comments (0)
Categories: Forecasts
        

And we earned it. After a couple of weeks of cool, gray and wet April weather, we have finally shaken it all off. The next few days look absolutely perfect. Highs in the 70s, lows in the 40s, and nearly perfectly clear skies, day and night. Here's the official forecast.

Highs in the 70s will put us as much as 10 degrees above the long-term average for these weekend dates. Average highs for this time of year are 66 or 67 degrees. The average low is 44 degrees. The warmer weather will help to pull this April out of the basement. So far, it remains the coldest April in Baltimore's weather books, which stretch back to 1871.

The average temperature for this month is just 45.6 degrees (through Thursday), according to the National Weather Service. The last time a Baltimore April got even close to that was a century ago - in 1907 - when the month ended with an average temperature of 47.8 degrees. It was even cooler in April 1874, when the city averaged an even 47 degrees. Here is the temperature data.

With the skies so clear this weekend, I was hoping we could catch a nice pass by the International Space Station. But, while the station is in the evening sky this week, its track is fairly low to the horizon, and may be hard to spot. A better opportunity will come next Tuesday evening, if skies stay clear. Watch this space.

The best sight in the evening sky tonight will be a slender crescent moon passing close by the planet Venus, in the western sky after sunset. The pairing was beautiful last night. The moon will have climbed a bit higher by tonight, above Venus. Late evening commuters (like me) will have another lovely view.

Another option, for the insomniacs among us, will be the Lyrid meteor shower. It's a small one, but with the moon setting early, and the very clear skies, it could be a pleasant way to pass the (very) early Sunday and Monday morning.

Posted by Frank Roylance at 11:18 AM | Permalink | Comments (0)
Categories: Forecasts
        

Were it not for the Virginia Tech story, the top national news this week might well be the beating they're taking in New England from the nor'easter that tromped through here Monday. Here's the Boston Globe story. Be sure to click on the "readers photos" link. There's video linked from this storm coverage page.

The intense low at the center of this storm continues to spin offshore, and we remain under its influence. Early Monday it brought us the lowest barometer reading at BWI in 15 years, and our cool, gray skies since then are coming to us from the north as winds sweep counter-clockwise down the west side of the circulation. Here's the radar loop. Here's the view from orbit.

Posted by Frank Roylance at 11:13 AM | Permalink | Comments (0)
Categories: Cool pictures
        

There's a big wildfire burning in Georgia, and the smoke plume extends clear into northern Florida. Get a load of this satellite image. Here's how it looks close up. And here's how the Florida Times-Union, in Jacksonville, covered it.

Posted by Frank Roylance at 11:21 AM | Permalink | Comments (0)
Categories: Cool pictures
        

It may not have buried us in snow, like the President's Day Weekend Storm of February '03, or flooded the bay shore like Isabel did back in September '03 (that was a bad year, wasn't it?).

But the nor'easter than soaked us over the weekend and knocked out electricity for thousands produced the lowest barometric reading at BWI in more than 15 years.

The barometer here at The Sun dropped to a low of 29.092 inches at 4 a.m. on Monday, the 16th. The official reading out at BWI, according to the National Weather Service, was the same, 29.09 inches, at 5 a.m.

The last time the barometer sank that low at BWI, forecasters said, was on Jan. 14, 1992. I checked our Evening Sun clips for that date and the dates immediately after. They told of a "long overdue blast of winter weather" that roared through the region with thunderstorms and gusts to 61 mph at Westminster. Power lines and trees fell, knocking out power to 16,000 BGE customers. Tornado watches went up across the Eastern Shore. Temperatures dropped from the mid-60s to the mid-30s.

The wild weather was our share of a powerful winter snowstorm centered in the Midwest that closed schools, stopped traffic and set cold records as far south as Louisiana. In Central Maryland, the storm's passage left us in bitter arctic cold, with overnight lows in the teens. Snow squalls slicked roads and snarled traffic. Garrett County had several inches of snow.

Posted by Frank Roylance at 10:40 AM | Permalink | Comments (0)
Categories: By the numbers
        

Live for the weekend, folks, because there's no relief until then from this cool, gray, clammy weather. Here's the official forecast.

For now, we're stuck under the influence of the return flow from that big low - the nor'easter - that pummeled us over the weekend. Here's the radar loop. You can see the counter-clockwise flow that's bringing the cool air down from the north. Throw in the occasional rain or showers embedded in that flow, and we get wet.

By the end of the week we should come under the influence of high pressure. Skies will clear and the high's clockwise spin will start to bring us warmer air from the south. 

It's been quite a month so far. April 2007 has already posted three daily weather records.

April 7: Greatest snowfall ever recorded for Baltimore on this date - 0.2 inch, tying the mark set in 1972.

April 9: Record low temperature for the date. The 26-degree reading at BWI bested the 28-degree mark set for the date in 1917. 

April 15: A record rainfall for the date - 2.46 inches. That broke the 1.82-inch mark established in 1983.

Temperatures so far this month are averaging 45 degrees - 6 degrees below the average for an April in Baltimore. We've had 4.41 inches of rain, almost three inches above where we should be by this date in April.

Posted by Frank Roylance at 5:45 PM | Permalink | Comments (0)
Categories: Forecasts
        

We're back, having reluctantly left a place with water all around it, sunshine, and temperatures stuck between 75 and 85 degrees every day, only to return to wet, cold and gray Baltimore. And I thought April was Maryland's pleasantest month...

But I digress. First order of business this morning is to correct an obvious error on the print editions' Weather Page. Somehow, our weather data vendor - Weather Central - came up with bogus data for the record highs and lows for April 16 at BWI.

The paper says the record high was 91 degrees, set in 2002. The stated record low for an April 16 was 2 degrees, set in 2003.

As one alert reader has already pointed out, we have never come close to 2 degrees in April. The record April low for Baltimore is 15 degrees, set on April 1, 1923. The actual records for Monday's date are 90 degrees (set in 2002) and 30 degrees (set in 1962). We have asked Weather Central for an explanation. We are not happy.

In the meantime, we are working this week with new blog software. It will take me a bit of time to get comfortable with it, so bear with me if things are a little rocky at first. Still trying to figure out how to insert images and paragraphs. Sigh.

So what the devil happened to our weather while I was away? Snow? Cold? Four inches of rain? Must everything fall apart when I leave the control room? Well, I'm back, and by the weekend we should have things looking brighter, with more sunshine and temperatures back to around 70 degrees or better for the opening weekend at Pimlico. Here's the official forecast.

Posted by Frank Roylance at 10:46 AM | Permalink | Comments (2)
Categories: Notes to readers
        

With April getting unseasonably cold, freeze watches posted for Central Maryland, and rumors of snow in the air, it's time I slipped away from the WeatherBlog control center. I will be hunkered down in my Unseasonable Weather Bunker, nicely sheltered from the cold, getting some much-needed R&R with a teacher I know.

While I'm gone, the Blog will go silent. But I invite you to check the forecast on your own. Click here for the main page of the National Weather Service's Sterling, Va. forecast office. Then, on the map, just click on your hometown and the forecast will appear.

For night sky forecasts, try the 2007 backyard stargazing calendar we published at the end of December. Here's a link.

Looking for the International Space Station? You're in luck. The ISS is back in the evening sky. Look for two good passes next week, on the 9th and the 11th.

On Monday, the 9th, the station will rise above the southwest horizon at 9:09 p.m., zipping over Mississippi and Alabama at 17,500 mph, headed for the skies over Maine. Watch for it to soar through the constellation Orion, rising as high as 62 degrees - two-thirds of the way from the horizon to the "zenith" - straight up. It will look like a steady white star hustling toward the northeast. But then it will vanish suddenly into the Earth's shadow and disappear at 9:12 p.m.

On the 11th, the ISS will fly nearly the exact same trajectory, rising above the southwest horizon at 8:14 p.m., this time sailing clear across the sky. It will pass almost directly over Baltimore (a bit to the north and west), and head off toward the northeast horizon, disappearing at 8:20 p.m.

You'll need clear skies, of course. And a sharp-eyed child, eager to spot it first, will help. Good luck.

The Blog will revive on the 17th.

Posted by Frank Roylance at 6:26 PM | Permalink | Comments (0)
Categories: Notes to readers
        

And you thought spring was here for good. Hah! On Wednesday we can expect the weather doors to swing wide, allowing an arctic air mass born and bred in Northeast Canada to barrel through. You'll know the front has arrived by rain, and maybe the noise. Thunderstorms could herald its passage.

And the cool weather will stick around well into next week. Look for lows to sink to the 20s by Thursday night, with a chance for snow showers on Saturday. We're talking about temperatures 20 degrees below normal for this time of year. Check out this forecast for Garrett County.

Here's our official forecast from Sterling. Here's AccuWeather's take on this brutal turn of events.

Posted by Frank Roylance at 6:25 PM | Permalink | Comments (2)
Categories: Forecasts
        

Continuing warmth in Atlantic surface waters and the dissipation of El Nino conditions in the Pacific will combine to bring the U.S. a "very active" hurricane season in 2007, according to hurricane forecasters at Colorado State University. That is, busier than last year, when no hurricanes made U.S. landfall, but not as active as 2004 and 2005, when storms pummeled Florida and devastated New Orleans and the Gulf Coast. (That's 2005's Katrina at left.)

The CSU forecasting team of Phil Klotzbach and William Gray today boosted the numbers they forecast in December for the upcoming Atlantic hurricane season, citing the faster-than-expected disappearance of the El Nino conditions in the Pacific. They're now anticipating 17 named storms between June and November, besting the long-term average of 9.6. Of those 17 storms, the forecasters expect nine will grow to hurricane strength (The average is 5.9.) Five of those will become Category 3 storms or stronger. (The average is 2.3.)

The CSU forecast also predicts a 74 percent chance one of those major hurricanes will strike somewhere along the U.S. Coast, higher than the average of 52 percent for the past century. There is a 50 percent chance one will hit somewhere on the East Coast, including Florida, more than the 31 percent average for the last century. And, there is a 49 percent chance the Gulf Coast will see a storm that big, the forecast states, up from the long-term average of 30 percent.

Here is the full report. Looking back, Klotzbach and Gray fell far short of predicting 2005's record hurricane season, but so did everyone else. Their forecasts in December 2005, April and June 2006 also badly over-estimated the actual storm counts in last year's season. That season fizzled, meteorologists say, because of the unanticipated development of El Nino conditions in the Pacific, and dust storms from North Africa that blew out over the eastern tropical Atlantic.

This year, Klotzbach and Gray anticipate neutral, or weak-to-moderate La Nina conditions in the Pacific, which would support hurricane formation in the Atlantic. The Atlantic basin also continues to experience unusually warm surface waters, which is another factor supporting hurricane formation. The Atlantic Basin has seen unusually active hurricane seasons in most years since 1995 thanks to warm water conditions there, the CSU team says. That trend, part of a long-term Atlantic climate cycle, is likely to continue for decades to come.

Unlike many climate scientists, Klotzbach and Gray say there is insufficient scientific evidence that global warming is playing a role in the recently heightened hurricane activity in the Atlantic. Their reasoning can be found in their current forecast.

Posted by Frank Roylance at 11:38 AM | Permalink | Comments (0)
Categories: Hurricane background
        

Driving down the JFX this morning you couldn't help but notice it. We cruised south under sunny, blue skies and mild temperatures. But as we neared downtown, the air grew suddenly colder, and the blue sky became obscured by low clouds and fog. That's the "marine layer" - a chilly layer of air, a few hundred to a few thousand feet thick, cooled and moistened by the ocean. It runs up onto the land, bringing a chill fog. Above and beyond the marine air, however, the sun is shining and temperatures are dramatically warmer. Here is what is looks like this morning from orbit. You can see the cloudy marine layer retreating across Delmarva.

At left is a nice photo of the cold, marine-layer fog from the Los Angeles Astronomical Society. And if it felt like San Francisco downtown this morning, it's no accident. The West Coast is frequently assaulted by a cool, foggy marine layer blown ashore by westerly winds. It usually retreats, or dissipates as the morning wears on. And the sky does appear to be brightening over The Sun building as I write.

Temperatures at Calvert & Centre streets fell from 70 degrees at 11 last night, to 61 degrees by 5 a.m. Then the marine layer shoved its way ashore, and the mercury dropped to 51 degrees at 8 a.m. Two hours later it's still only 53, but climbing. Deeper in the marine layer, Ocean City remains gray and 46 degrees.

Posted by Frank Roylance at 10:28 AM | Permalink | Comments (0)
Categories: Events
        

So, April begins, and it looks as though the poet was right. After a brilliant start, with sunshine and temperatures in the 70s, we're looking for cruel lows in the 20s by week's end, with the threat of snow showers in the mountains.

Such excursions into the 20s aren't unusual in April. The record lows for the month range from 15 degrees on April 1, 1923, to 35 degrees on the 27th back in 2001. Snow is quite possible in April. While the average total snowfall in April is just a tenth of an inch, an April Fools storm in 1924 dumped 9.4 inches on the city. Only two other dates have seen more than an inch of snow - on the 10th and 11th in 1894. Only seven dates in April have seen no snow since record-keeping began.

Hot weather is also quite possible, on any April date. The record highs range from 83 degrees early in the month, to 94 degrees, reached on four separate days later in April.

The norms, however, are far milder. The normal afternoon highs rise through the 60s as April progresses, from 60 on the 1st to 69 degrees by the 30th.

The normal overnight lows start out at 38 degrees, and rise to 47 degrees by month's end at BWI.

March ended Saturday night having delivered a surplus of moisture - 4.17 inches. That's a quarter-inch above the long-term averages. The airport set a new record for precipitation on the 16th, with 2.14 inches. That snapped the old record of 1.14 inches, set on that date in 1876.

We had 1.4 inches of snow, on the 7th and the 16th. You can watch the snow retreat northward across the continent during March in this loop generated from satellite snow-cover data.

Temperatures in March averaged 45.1 degrees. That was 1.4 degrees above the norm at BWI. We set a new record high for a March 14, when the mercury reached 83 degrees. That broke the old record of 81 degrees, set on that date in 1990. The low for the month was 14 degrees, on the 8th. That gave the month a temperature spread of 69 degrees.

Here's the month's summary from the NWS folks at Sterling:

"MARCH TURNED OUT TO BE A ROLLER COASTER RIDE AT BWI.
TEMPERATURES REACHED 70 DEGREES SEVEN TIMES DURING
THE MONTH...HELPING TO MAKE MARCH THE 45TH WARMEST ON RECORD.
HOWEVER...ON THE FLIP SIDE THERE WERE SOME VERY COLD AND SNOWY TIMES
AS WELL. FOR EXAMPLE... 0.8 INCHES OF SNOW FELL ON THE 7TH AND
THIS WAS FOLLOWED BY RECORD COLD ON THE MORNING OF THE 8TH."

They're wrong about that last item. The low of 14 degrees on the 8th was not a record. The record for that date in Baltimore is 10 degrees, set in 1960. Nobody's perfect.

Here is your guide to the night sky in April, from the Hubble Space Telescope Science Institute. And here's a link to this year's Stargazer's Calendar. Enjoy.

Posted by Frank Roylance at 11:19 AM | Permalink | Comments (0)
Categories: By the numbers
        

You'll not find better weather anywhere than these next two days in Baltimore. In my book, April is the best month of the year in Maryland. The place is awash in blossoms. They're calling for blue skies and highs today and Tuesday in the mid-70s. Perfect. But it won't last. Sorry.

At midweek we'll get a cold front through the region. Late Tuesday and Wednesday there's a chance of showers or thunderstorms, with cold air pouring in to the region from northwest Canada. There's even mention of snow showers in the higher elevations. Don't put out any tender plants just yet. The forecast lows for the Baltimore region slip down into the upper 20s starting Thursday night. AccuWeather says Easter here could be colder than last Christmas.

Posted by Frank Roylance at 10:25 AM | Permalink | Comments (0)
Categories: Forecasts