Get your shorts out. Stock up on sun tan lotion. Make sure you have ice and cold drinks. Because some of the warmest April/early May weather we have seen in over a decade looks increasingly probable for Wednesday and Thursday of the upcoming week. Maybe even reaching the big EIGHT-OH!
At this point most of the leading models are going for this warm forecast, so I feel pretty confident telling you about it.
Let me show you the 12-km UW WRF model forecasts for this week. First, we have to get through a some rain tonight and showers on Sunday...sorry folks. April showers are required. But then on Monday and Tuesday, upper level ridging (high pressure) start building over the eastern Pacific. Here is the upper level (500 hPa, around 18,000 ft) maps for 5 PM Monday and 5 PM Wednesday. The will be a huge ridge developing over the West Coast with very large north-south extent.
Let's follow the 2-m (surface) air temperature and near surface (10-m) winds that is forecast by the UW model. First, at 5 PM Monday: 56-60F over western Washington and a bit warmer near Portland and the Columbia Basin.
Tuesday afternoon, a notch warmer,with 60s over western WA and 70s to the east.
And then Thursday at 5 PM. What can I say? We haven't seen April temperatures like this in a decade. A number of folks away from the water could get to 80+F that day. I suspect that a 24-h virus may be rampant that day.
At this point in time, the official outlets are going conservative, as they should. The National Weather Service is predicting 79F for Wednesday and 81F for Thursday. Very reasonable.
The Weather Channel is slightly cooler than the NWS:
For those of you those like weather statistics, my colleagues at the National Weather Service have noted that the average first day getting to 80F in Seattle is May 23rd....we will do much better that that this year! And let me provide an important warning. Just because we are going to have a few summer-like days, don't think you can put those tomatoes outside yet: cool weather will come back next weekend!