A few morning showers ended hours ago and now sunshine and clouds is the rule for the start of summer. While meteorological summer began on June 1st and yesterday was the summer solstice, it’s actually today that many consider the first full day of summer and for students, this is the first full week with no school.

The weather pattern is on the edge of a major shift. This shift is going to possibly bring record breaking heat to part of the Rocky Mountain area west to the Pacific while the opposite is likely to be true from the Ohio Valley to New England.

The National Weather Service in Pendleton, Oregon is already raising awareness about the coming heat this weekend.
Meteorologists often use terms like average, normal, typical, and seasonal.

As I often point out, all of the so called regular patterns are basically a collection of extremes over time. Summers are cool, hot, wet and dry. It’s rare we, or many places in the United States, see long stretches of weather where the high and low are average or the amount of rainfall is close to what the 30 year averages say we should be experiencing. This fluctuation from extreme to extreme is one reason Mark Twain’s famous quote,

“If you don’t like the weather in New England now, just wait a few minutes” still resonates today.

Tuesday Storms
The first three days this workweek feature warm temperatures and moderate levels of humidity for today and Tuesday. Tomorrow a frontal system will cross the area and bring with it a chance of thunderstorms, some of which might be severe.

Predicting the specifics of severe weather two days ahead of time isn’t easy, but I can look at the forecast state of the atmosphere and see conditions will be favorable for possible thunderstorms. On Tuesday we will have warm moist air in place with less humid air to the west. As these air masses clash, thunderstorms will likely result.

Wednesday and Thursday are both nice days with sunshine and lower humidity. It will still be seasonable warm, but certainly not hot at all. Late this week a trough or dip in the jet stream will introduce cooler air into New England. Cool air in late June and early July isn’t cool, but May standards, but it could means high temperatures remain in the lower to middle 70s for a few days. Readings that cool with the sun so strong is as amazing as seeing a 70 degree day in December when the sun is so weak.

It’s not only going to be cooler than average at the end of the week and to start the weekend, there will be some shower activity. I can’t with confidence predict the timing of showers Friday through Sunday, but like the thunderstorm prediction for tomorrow, the models indicate a positive set-up for shower activity late this week.

Cool Pool
One of the maps I review to help forecast temperatures at the ground is the map showing temperatures at about 5,000 feet. If readings up there are cool or warm it’s a good indication of the potential for temperatures here. The map below shows temperatures at 850 millibars up or about 5000 feet for early July.

These temperatures are in degrees Celsius. Notice the coolest air is centered in pool over the northeast in similar fashion to February and March. It’s interesting although we had a warmer than average May, it appears, at least for the now, we aren’t going to break into a prolonged hot pattern. This is probably welcome news for heat haters, but not good news for beach goers who love the summer sizzle.

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