Mar 13, 2012; 10:18 AM ET
Tuesday, 11:45 a.m.
Monday turned out to be a record-setting day in the Northeast, as new record highs were established in Bangor, Maine (62); Boston, Mass. (71); Providence, R.I. (72); Hartford, Conn. (74); Albany, N.Y. (69); and Syracuse, N.Y. (68). And they were not alone on the Hit Parade of Warmth, as parts of Florida, Kansas, North Dakota and Missouri all had record highs.
Before this run of May-like warmth is over, the daily record chart will read like Billboards' Top 40. Or maybe top 100 on some days! Here's just a sample of what is being forecast off the GFS ensembles for Saturday:
That's just one day in a string of many days with a similar look. There's no hint of arctic air to be found from the Rockies to the East Coast, and from the Gulf Coast to the northern reaches of Ontario and Quebec. And with an upper-level ridge of high pressure building going into the weekend, the air mass that is already warm should get even warmer. Look at the GFS 500mb forecast for Sunday evening:
Now compare the 850mb temperatures for Sunday evening:
Let me do a little math here to drive home the point. We are now in spring (officially at 1:14 a.m. Eastern Daylight Time next Tuesday for you purists). The sun is getting higher in the sky daily steadily, if not rapidly. That means the sun is up longer and is more effective at stirring up the atmosphere. In other words, it's easier to mix out the warmth aloft to the surface. Typically in spring and summer, a rough guesstimate is to take the forecast 850mb temperature in Celsius and add 15C to get an approximation of the surface temperature.
This 'dry adiabatic' process is made more effective with full sunshine and where there's a good wind blowing and is enhanced if that wind flows downhill from any higher elevation. Add in the fact that the trees are virtually devoid of leaves at this point in time, and you have a very solid recipe to reach the full potential of the air mass given the constraints of the forecast 850mb temperatures.
So, using that, let's cherry pick a couple of cities to cite as an example on Sunday. In Detroit, the forecast 850mb temperature is roughly 11C. Add 15, and that gets you to 26C, and that translates to 79F! The average high Sunday in Detroit? 47.
How about Sioux Falls, S.D.? Forecast 850mb temperature is 14C. Add 15, and you get 29C. That translates to 84F, 40 above normal for the date!
If you look carefully at the chart above, there are some wind barbs on it, an indication of the forecast 850mb wind speeds. In the Plains and Mississippi Valley, they're anywhere from 30 to 50 knots, further supporting the idea of record warmth. The only thing that would hold these areas back from reaching those insane highs would be clouds and precipitation. Even so, that probably means the nighttime lows will stay in the 40s and 50s, if not some 60-degree readings in places like Kansas City and maybe St. Louis.
Farther east, there's much less wind aloft underneath high pressure, surface and aloft. That means less effective mixing, and areas anywhere close to the Atlantic Seaboard will have to deal with sea breezes off the chilly western Atlantic. At last check, water temperatures were no better than the 40s, so once the air heats up into the 50s inland, that sea breeze should kick in. Even though it will still be milder than average by a far margin throughout the mid-Atlantic and New England, it won't be anything close to areas west of the Appalachians.
Even there, though, there will be a couple of spikes of notable warmth. One will be this afternoon. Another will probably come during the early to middle part of next week when the surface high slips south of New England, and westerly winds can overpower any sea breeze and bring some amazing warmth to southern and eastern New England. In fact, if the forecast 850mb temperatures of greater than +12 come to pass, it could reach 80 along the eastern New England coast next Wednesday and should easily reach the 80s inland.
Let the Hit Parade of Warmth continue.
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