Depending on where you live in the area the first time you hit 90F degrees for the year is somewhere from late May until mid-June. Portland’s average first 90F is June 9th. We have seen 90F readings as early as April (2009) and made it through the entire month of June free of 90F. Back in 2006, we didn’t hit 90F until July 14th.

90F is of course just a number, it can feel hotter at 85F than it can at 90F depending on the humidity. Also, the number of hours we experience 90F is a large part of how the overall day seems. On a day where we reach the mark at 9AM, it’s certainly a lot more unbearable than if we hit it for just a few hours around 1PM and it’s over by 5PM.

Dew Points are also a big player in how we all manage a 90F degree day. Tomorrow, while dew points will certainly be in the 60s, they won’t reach the oppressive 70s. There is an enormous difference in the amount of moisture in the air with a dew point of 65 versus 72. This difference makes the heat much more tolerable.

I’ll be updating the forecast @growingwisdom on Twitter.

Tomorrow won’t reach 90F, but it’s going to be very warm. I don’t expect any official readings of 90F tomorrow, but Sanford will likely be the closest. Since we won’t reach 90F and I don’t see a 90F degree day for a while, we will continue June free of that sort of heat.

The chart below gives a general idea of temperatures and dew points for tomorrow. Notice in Portland, this model predicts a high of 84F. I like the mid-80s in the summer, it’s warm, but not so hot you can’t enjoy it.

Portland warmth

A few light showers occurred this morning, but not everyone saw them. Skies will be partly sunny today.

There is another chance of showers late tonight as part of the jet stream that is favorable for the formation of storms whizzes over us at around 30,000 feet. Tomorrow afternoon a cold front brings an end to the brief heat and humidity with another round of showers and storms possible. The exact timing of the front will help determine if these storms become strong or just push through rather uneventfully.

Behind the front drier and cooler air comes in for the rest of the week and the weekend. Highs Thursday will reach the upper 70s to lower 80s, but likely staying in the lower and middle 70s Friday and Saturday. There won’t be any noticeable humidity for the weekend and with brilliantly blue ski another winner is on the way.

Lastly, the twin tornadoes in Nebraska were quite a site yesterday. If you haven’t seen the video on this storm it’s worth watching. Unfortunately, for the little town of Pilger Nebraska this storm went right through. The town is quite small only having 378 residents according to their web site. Twin tornadoes are very rare and it’s even rarer they would be captured on video.

Ironically, it’s been a very quite tornado season. This week isn’t over yet and I suspect more severe weather is on the way for parts of the Midwest and even spreading the east coast. Tomorrow’s map shows a slight risk of severe weather for swath of the country where about 78 million people reside.

weds severe pos