It's pretty early in the season for such Cape Verdean storms to spin up. Not sure whether that suggests anything about what lies ahead for us, but as they say in the editorials, this bears watching.

Here is the latest advisory on Bertha. Here's the latest storm track forecast. And here's a view form space: 

After a cool and very wet May, June at BWI resumed the warm pattern that has prevailed here since the beginning of the year. Temperatures at the airport averaged 75.3 degrees last month. That was 3.5 degrees above the long-term average of 71.8 degrees, and made it the warmest June since 1994, and the fourth-warmest in Baltimore in 65 years.

1943:  79.8 degrees

1994:  77.2 degrees

1949:  75.6 degrees

2008:  75.3 degrees

So far this year, only May ended cooler than the norm.

Precipitation was close to the June average for BWI, at 3.70 inches. The long-term average is 3.43 inches. Ten days saw measurable rainfall.

The high temperature for the month was 96 degrees, on the 10th. The low was 52 degrees, on June 18. No new records were set.

Not unexpectedly, given the warm temperatures, we ran well ahead on cooling degree-days, a measure of the demand for energy for cooling. We were up 34 percent over the average for June.

Looking ahead, July is typically our hottest month, with average temperatures peaking third week in the high 80s. The all-time record high temperature for Baltimore is 107 degrees, set on July 10, 1936. Only 7 dates have record highs of less than 100 degrees.

The coolest record daily high for the month (and therefore the easiest record to break) is 97 degrees, set on July 12, 1908 and July 24, 1987.

The record low for the month in Baltimore is 50 degrees, set on July 1, 1988 and again on July 3, 2001. The warmest record low is 59 degrees, set July 19, 1962.

The wettest July on record for Baltimore was in 1889, when 11.03 inches fell. The driest was in 1955, with just 0.3 inches in the gauge.

Right now we're continuing to enjoy the benefits of the high pressure system that's brought us clear skies and relatively low humidities for the last couple of days. (Enjoyed a gorgeous day kayaking out on the Gunpowder River below Monkton yesterday - cool and dry. The river seemed a bit low, but we spotted an otter - a first for me - and plenty of geese and deer, blue herons and kingfishers. Trout seemed happy with the day, too.)

Tomorrow will be the hottest day of the week, with a forecast top of 92 degrees at BWI. 

The 90s are hot for any time of year in Baltimore. The average highs at this time of year are in the mid-to upper 80s. By Friday we'll be back down in the 80s. But the high will be shoving off to the south and east, and we'll come under the influence of a cool front slipping in from the north and west. The front will stall here Friday, and storm systems creeping along the front will mean an increased risk of showers and thunderstorms right through the weekend.

Forecasters out at Sterling say they're not expecting widespread severe storms and flooding out of these circumstances. But we could see "training" storms - thunderstorms and heavy showers that move across the region along a persistent track (like a train!). That often means large amounts of rain accumulating in some locations, while other spots see much less. It's too soon to know just where such training might occur.

In the meantime, hurricane forecasters are watching a tropical wave that's developing off the west coast of Africa, near the Cape Verde Islands. It's early in the 2008 season to see tropical weather cranking up in the far eastern Atlantic. Usually such storms - the sort that can grow to dangerous dimensions as they cross the tropical Atlantic - don't appear this early. They more typically become a problem in late August or September. Some of these "Cape Verdean" hurricanes can sweep north of the Caribbean and track up the East Coast, threatening landfalls from Florida to New England. We all remember one of them - Isabel - which struck in North Carolina and sent a storm surge up the Chesapeake. It flooded the Inner Harbor, Fells Point, Bowley's Quarters and many bayside communities back in September 2003.

But my guess is this is merely a prelude. Everybody's watching for ther season to get started. So far all we've seen has been Tropical Storm Arthur, an oddball that popped up on May 31, just before the official start of the Atlantic season on June 1. It was a small storm, but deadly. Fifteen inches of rain fell in places as its struck Belize and Central America. Five people died in Belize and damages there alone came to $78 million.

This storminess off the African coast is just the first patch to catch our attention since Arthur. But stay tuned.  The tropical Atlantic is pretty warm now. Here's the sea-surface temperature map. Anything above 27 degrees C. (the tan within the brownish band) is 80 degrees F or warmer. That's premium-grade hurricane fuel.   

Pretty sure that's Johns Hopkins Hospital at the end of the arcs. They oughta buy this image for their annual report. On the other hand, I believe the long, low building at lower right is the state's troubled Juvenile Justice building. Maybe there's hope for the place, or at least its residents.

Now, back into the Wormhole...

Theorists say the blogger can be expected to be eclipsed by the glare of his daughter's happiness, emerging again on the other side no sooner than July 2. Unfortunately, his wallet will be crushed into an infinitely small singularity with zero mass.

Watch this space for further developments. 

The prognosticators out at Sterling say the delightful high-pressure system that has been parked here for several days, delivering warm, dry, sunny days and cool nights will begin to shove off after today.

As it departs, we will fall into the return flow from its clockwise rotation. That means we'll be getting warmer, wetter air from the South; highs will slide into the 90s; and all this heat and humidity will increase chances for afternoon and evening thundershowers every day from tomorrow through Monday.

Of course, Saturday is the only day we care about here. My daughter is getting married (did I mention that?) and the forecast calls for a high of 91 downtown (actually a tad cooler, or less stifling than out at BWI airport) with a 40 to 50 percent chance for showers or thunderstorms during the afternoon and evening.

Shrewdly, we've planned the ceremony to be outdoors. So I'm looking at the "mostly cloudy" forecast and I'm thinking, 'OK, we don't need direct sunshine heating our guests, or our bride.'  Her mother and I were married in cloudy, muggy weather, and that's worked out fine.

And by 7 p.m. it should be a shade cooler than 91, right?. Maybe 85? We'll take 85. Rain? OK, we can handle rain if it comes early in the afternoon and leaves us time to wipe off the seats. Might even cool things off a bit. A rainbow would be a very cool bonus. MEMO TO WEDDING PLANNER: Look into the rainbow. A single arch will do. Alert the photographer. Just send me the bill.

Rain at showtime will chase us indoors, of course. That would be too bad, considering our investment in the location and the view, and the chairs and the platform. But at least we have a Plan B. Rain after the ceremony is OK. Rain with a power failure during the reception and eating and dancing, however, especially an extended power failure, is unacceptable. MEMO TO BGE: We'll need trucks and crews on standby. I'm thinking something like the Verizon network folks on those TV ads. Just send me the bill.  

Rainbows are so striking, and unusual, that we long remember where we were and what we were doing when we spotted them. I can recall a rainbow that appeared after my wife and I arrived in Bar Harbor, Maine, for our honeymoon. Seemed like a good omen, and we're still hitched after 38 years. I can remember a spectacular double rainbow that astonished our kids (and us) during a summer camping trip in the 1980s. We were driving south from Flagstaff, across the desert, after a visit to the Grand Canyon. We just pulled over and gawked.

Have any special memories of rainbows you'd like to share? Leave a comment.  

There was a double rainbow yesterday in Washington, and CapitalWeather.com has posted a terrific photo gallery. There's a link in the comments below.

]]> http://weblogs.marylandweather.com/2008/06/rainbow_over_baltimore.html http://weblogs.marylandweather.com/2008/06/rainbow_over_baltimore.html Cool pictures Tue, 24 Jun 2008 10:10:18 -0500

Forecasters out at Sterling are on the lookout for showers and thunderstorms today. They say conditions are ripe for some severe storms to develop as heat, humidity and an approaching cold front team up to make our afternoon and evening positively electric.

The cold front was out over the Ohio Valley early this morning. But it's headed this way, and due to crash through after 2 p.m. Showers and thunderstorms will boil up along the front or just ahead of it. This morning's discussion says "in the late afternoon/evening storms should begin to develop along/ahead of the actual frontal boundary. Damaging wind gusts and large hail will be possible within any severe storm that develops."

You can track conditions in downtown Baltimore via The Sun's own weather station, at Calvert & Centre streets.

Scattered showers and thunderstorms could even linger into Tuesday. But as high pressure works its way into the region, Wednesday begins to look like the best bet for outdoor activity this week. Temperatures will be close to normal for this time of year - near 87 degrees. But humidities should be relatively low, and sunny skies will dominate.

Then things begin to slip. As the high moves offshore, we get into the familiar "return flow," meaning that the clockwise circulation around the high begins to draw more hot, humid air up from the South. That, in turn, increases our risks for showers and thunderstorms. Forecasters put that risk at 30 percent for every day from Thursday through Sunday. Daytime highs will creep to 90 by Thursday and hang in that neighborhood right through the weekend.

Sooprise! Sooprise! Hot and humid on the Chesapeake in the summertime! What were we thinking when we scheduled an outdoor wedding for June 28? NOTE TO WEDDING PLANNER: Get more ice for the beer. Just send me the bill.

So far, the week ahead looks relatively mild, with seasonable highs in the mid-80s, and a 30- to 60-percent risk for showers and thunderstorms nearly every day and every night through Tuesday. Then things get even better. No rain, no lightning, just mostly sunny skies and mid-80s highs through Friday.

But it's Saturday we care about, folks. The wedding is outdoors, at 7 p.m. It's the evening after the latest sunset of the year, so the sun will still be quite high. But temperatures should be moderating by then. I'm looking for 80 degrees or cooler, please and thank you. There's no AC under that white gown. Thunderstorms are OK so long as they come after we've gone inside to party. (And so long as the power doesn't go out. That happened at a wedding we attended last year. Not good. Paying a DJ. Need the juice.)

We'll even welcome a few clouds. Cuts the direct sunshine and cools the guests. A nice breeze would be desirable, say 5 mph or so. Enough to push the mosquitoes away, but not enough to blow out the wedding day hairdos or knock over the flowers.

LA Times file photo 

MEMO TO WEDDING PLANNER: See above. Think you can manage all that? Very important! Just send me the bill.

We have visitors from Sweden with us this week. For them, tonight is the night to celebrate Midsummer's Night and dance around a pole with candles in their hair. Or something. That's MID-summer's Night. Not BEGIN-summer's Night.

They conceded to us that they, too have been confused about why summer BEGINS on the date called MID summer, when the sun is in the sky longer than any other. And where they're from, it never does get truly dark at night at this time of year. 

We were visiting them one summer many years ago in Sweden, and we all went to dinner at the home of some friends. We drank. We ate. We talked alot. And each time I looked out the window it was dimmer, but still light. My wife and I, accustomed to summers living around a latitude of 40 degrees or so, figured it was, maybe, 9 p.m.

When we finally looked at the clock we were astonished to discover it was past midnight! We were dining at around 57 or 58 degrees north latitude, the equivalent of Churchill, Manitoba, on Hudson's Bay. The sun was down - we weren't above the Arctic Circle. But it was still twilight. I could have read a book without a flashlight.

Anyway, the idea that summer BEGINS around June 20 or 21 is a recent notion. Many of our ancestors did indeed see this as MID-summer. They used "cross-quarter days" - the midway points between the equinoxes and the solstices - to mark the beginning and end of the seasons. For example, by the Celts' reckoning, our summer began somewhere between the 4th and 10th of May, on a day they called Beltane. And it will end between the 3rd and 10th of August, on Lughnasadh.

Some also find it curious that the hottest days in Maryland - the warmest long-term daily average temperatures - are in mid-July, a month after the solstice. If the days are longest, and the sun is highest, and its rays most direct and intense around the 20th of June, why does this month not also produce our highest average temperatures?

The answer lies in the oceans. Literally. It just takes a few weeks for the increased solar energy falling on the Northern Hemisphere to heat the oceans to their maximum seasonal highs. That, in turn, delays heating of the atmosphere. It's like heating a pot of water on the stove. It takes a while on HI to get the water to boil. By the time temps reach their peak, the incoming solar energy is waning, and by late July, the oceans and air finally begin to cool again.

Anyway, enjoy the long day today. From here on until Dec. 21, the days only get shorter. And don't forget to get a look at the solstice moon tonight. It rises at 10:24 p.m. in Baltimore. It's just past full, but still a gorgeous sight in the east.  

Seems to me there have been some efforts to buy out a few of these places, and rebuild communities on higher ground. But it's clear we don't do enough of it. Instead, we spend our money on (ultimately) futile attempts to hold back the rivers and defy the storm tides. New Orleans is a classic example of a place that should never have been settled. Yet we rebuild, spending billions on levees that break and beaches that wash away, and flood insurance that just keeps on giving.

Consider this from Friends of the Earth:

"In 1966, a report to Congress by the Task Force on Federal Flood Control Policy gave the nation a lesson in flood control: don’t rebuild in high-hazard zones like coastlines and river deltas.  This lesson was reiterated in the 1973 Report of the National Water Commission.  Both distinguished panels found that despite the enormous flood control expenditures, flood damages were increasing. Both panels recommended that more attention be paid to relocation out of flood zones and called for greater emphasis on non-engineering solutions.  There is a growing body of evidence that healthy wetlands, in-tact dune systems and other natural ecosystems reduce storm and flood damage, but far too many tax dollars have been spent to destroy these natural systems to facilitate more development."

FOE makes the argument that global warming will make all this worse. But it's not necessary to invoke global warming here, although there are plenty of people ready to argue that more extreme precipitation and warmer, higher oceans will only increase the frequency of flooding events. Set all that aside. These rivers and shores have been flooding for eons. We're the new element there. And we're only building more costly infrastructure and adding more population to the riversides and coastlines. That's what's costing us so much more each time these events occur. And that's just dumb.

Anybody have any thoughts on this? Should we just help these people rebuild? Or should we help them move to higher ground? Leave the farm fields. Floods are good for them in the long run. But move the homes out of the rivers' path.

You can read more here.

It was 52 degrees at dawn on the WeatherDeck in Cockeysville, and 52 degrees also at Baltimore-Washington International Marshall Airport down in Linthicum. That was not a record for the city's official weather station, but it was a nice run at one. The record low for a June 18 in Baltimore is 48 degrees, set back in 1959. We still haven't touched 80 today - only the third day this month that's happened. It was 62 this morning at The Sun's weather station at Calvert & Centre streets.

The forecast low for tonight is 57 degrees, as temperatures begin to warm back toward more seasonable readings this week.

All this cool air is being delivered by a big low rotating north of Lake Ontario. That's dragging cool air in from the north and west, along with little disturbances that, with some solar heating, may trigger some showers or thunderstorms - a few perhaps with hail - as they roll by us. 

So far, however, the coast is clear. Just some cumulus clouds and patches of blue, clearly visible in the satellite image below.

They're calling for more of the same Thursday and Friday, with a risk of showers both days, and highs near 80 degrees. Saturday looks perfect for a wedding - sunny and 83 - but showers and thunderstorms become a risk again for Sunday.

The forecasters out at Sterling say today's weather will "usher in  a period of quite pleasant weather as we approach the solstice ... Dewpoints in the 50s today, temperatures 75-80. Breezy northwest winds. Enjoy." The summer solstice occurs at 7:59 p.m. EDT on Friday - the 20th (not the 19th, as I mistakenly said in a Weather Page item last Saturday). 

And here's a bonus. The west and northwest breezes will keep away the smoke from those wildfires burning down in Virginia and North Carolina. We've been getting some reports from vacationers and residents down there who have been dealing with the smoke. Not a pretty picture.

It's not perfect. We have a "slight" chance for showers and thunderstorms tomorrow and Thursday, and again on Saturday. But they're not a big worry. Mostly we're looking at pleasant temperatures, sunny to partly cloudy days.

Tonight and tomorrow evening we can also enjoy a spectacular full moon rising in the east. Astronomers say it will be perfectly full at 1:30 p.m. tomorrow, so at moonrise either tonight or Wednesday night it will be almost equally full. Moonrise in Baltimore is at 8:13 p.m. tonight, and 9:03 Wednesday. It's 10 minutes earlier in OC.

This is the 4th full moon since the Vernal Equinox, and before the Summer Solstice. That presents a problem.

Names for full moons (like the Harvest Moon or Hunter's Moon) are only available for three per season. In the old days, calendar writers reserved the term "blue moon" for these oddballs, and applied it to the third full moon in a season that happened to have four, according to Guy Ottewell's Astronomic Calendar. That would have made the May 20 full moon the Blue Moon, and this week's full moon would be the Flower, Rose or Strawberry Moon. (It's only in relatively recent times - since 1946 - that Blue Moon has been applied to any second full moon occuring in a calendar month.)

I think I've already used those names here for the May moon, so I'm stuck. This will either be a second Flower Moon, or a Blue Moon. Take your pick.  Or suggest your own moon name here. Like Smog Moon, Muggy Moon or Most Heat Moon.

Turns out, as forecast earlier in the week, we were downwind of several stubborn wildfires in eastern North Carolina and in the Great Dismal Swamp in southeastern Virginia. Those fires have been burning for quite a while now, and on Friday the winds finally shifted and began carrying the smoke up from the south. It eventually got all the way to New Hampshire before more wind shifts began to sweep it out over the ocean.

This sort of thing happens from time to time. Anybody else recall a weekend in 2002 when forest fires in Quebec began sending smoke wafting our way. It smelled like smokehouse in Baltimore, and the skies were noticeably beige as a result. 

And lots more probably remember the smokey stump dump fire in Clarksville 10 years ago this month, and another in Baltimore County that began in 1992, sent smoke drifting across the city, burned for 18 months and cost $3 million to control.  

Anyway, here's how the NC and VA fires looked Saturday, from NASA's orbiting Aqua Earth Observing satellite. They're still burning. I suspect vacationers on the Outer Banks are pretty sick of the smell. Anybody reading this on the OBX?