Maryland heads into the fryer this week
Hope you enjoyed the seasonable temperatures and low humidity over the weekend, because we are so done with that now.
Forecasters say Marylanders will be seeing temperatures and humidity rising all week, threatening 
the 100-degree mark by Thursday afternoon and topping it on Friday. We can count on another string of bad air days, too. Maryland west of the bay and east of Hagerstown is already under a Code Orange Air Quality alert today, meaning air pollution is expected to reach levels considered unhealthy for sensitive groups.
"This is genuinely hot air coming, with dew points somewhere around 70 degrees. Excessive heat watches may be needed by midweek," National Weather Service forecasters said in today's morning weather discussion.
And why not? On average, this is the hottest week of the year for Baltimore. The average daily high is 88 degrees. Daily record highs are all above 100 degrees from the 14th until the 29th, when we see our first record drop back to 99 degrees.
The culprit is our old summer friend, the Bermuda High. High pressure centered off the Atlantic coast by Wednesday spins clockwise, pumping hot, humid air our way from the Gulf of Mexico.
But first, we're looking at a forecast high for BWI-Marshall Airport today of 94 degrees. A cold front to our north is bringing some showers and thunderstorms to Pennsylvania later today, and we may see some clouds drift in from that later today. By tonight, showers and thunderstorms could reach communities in the northern and northeastern sections of Sterling's forecast area. Some could become severe, posing risks of flash flooding in the urban corridor. But the computers can't agree on the exact timing or severity of the storms. We don't need severe weather but we can sure suse the rain.
The weak cold front will deliver slightly cooler air for Tuesday, with a forecast high of 91 degrees and some lingering chance for showers at BWI. But that's just the starting point for steadily rising temperatures and humidity throughout the week and into the weekend.
The forecast calls for temperatures to reach 92 again Wednesday, then pop into the upper 90s to near 100 degrees Thursday and Friday before slipping back to 97 on Sunday. There's a small chance for some showers Sunday, too.
A high of 102 on Friday would break the Baltimore record for the date - 101 degrees, set in 1957.
Anyone ready for November?
Comments
I have been ready for November for quite some time! I better get the radiator fixed in my truck soon...running the heat to cool it down is not going to work by the end of this week!
Posted by: BaseballFan1425 | July 18, 2011 11:13 AM
gonna scare us frank with hot weather horror stories?
Posted by: malco49 | July 18, 2011 9:33 PM
Frank,
The average high for the period July 16 to July 25 is listed as 88 degrees, but those temps are rounded to the nearest full degree (87.51 and 88.49 would both round to 88, but 88.49 is hotter than 87.51).
Which day or days during the above period are actually, on average, the hottest?
FR: Always wondered about that. I'll see if i can find out
Posted by: Mike | July 18, 2011 11:06 PM
Am I hallucinating, or do I remember a long-term forecast, issued by some weather pundit earlier this year, saying that the Mid-Atlantic area could expect this summer to be cool and wet? I usally dismiss those long-range prognostications, but this one has taken on comic dimensions.
FR: If I remember correctly, it was a NOAA long-range forecast for June July and August. It said there were equal chances of the summer averages for precipitation and temperature being above, at, or below the long-term norms. But the region was closest to areas where they expected cooler and/or wetter than average weather. So far, we're hot and dry. But the summer is only half over. It may be too soon to laugh.
Posted by: BankStreet | July 19, 2011 9:42 AM
I saw heat index of 126 for Iowa yesterday, according to last night's TV weather report. Is that a record?
Whats the heat index record high for this part of the country?
FR: See Friday's print weather page for the answer.
Posted by: Capt Jack | July 19, 2011 10:38 AM