Some people think of Memorial Day weekend as the ‘unofficial’ start to summer but I’m going to cheat that start up a week and a half. By this Saturday, the ‘normal’ high temperature is 70 degrees. We know by the wild swings of Spring it is the extremes of temperatures (both warm and cold) that help determine that normal. However, as we get closer to the Summer Solstice those swings become less pronounced and our temperatures become a bit more consistent. Just look at how frequent 70 degree weather becomes over the next four months. I looked back at the records all the way back to 1903 and starting May 15th and going through the middle of September we reach 70 degrees or greater on 82% of the days. Roughly 8 out of every 10 days; a pretty good percentage.
Speaking of 70 degrees, with today’s 75 we have been 70 or above on 11 of the first 16 days of the month so we are already getting close to that 82% figure. The month of May as a whole is about three degrees above normal and that is in spite of the cool patch last weekend and early last week.
It looks like we will get into warmer and more humid air as we approach the end of the weekend and early next week so our average for the month is likely to climb.
We are getting closer and closer to the Memorial Day and even though that doesn’t figure into our 7 day forecast just yet we are still wrestling with what the 3 day holiday weekend has in store for us. I’ve seen the European model go from a troughy and showery pattern here in the East (Wednesday’s solution) to one where it is dry and cool to start with sunshine and milder weather to end things on Monday (Thursday’s and Friday’s solution). Now the GFS is starting to show the same thing. Here is a GFS forecast map 10 days out for Memorial Day Monday that we were looking at this afternoon.
On top of that, we have some agreement from the other main forecast model, the European:
Both of these solutions would mean sunshine and temperatures close to or a bit better than 70 degrees. I will caution, however, that this is still 10 days out in time and things can change. I’ve seen Memorial Day and Labor Day forecasts change 3 or 4 days out in time. Still this gives us some idea what systems we have to watch out for as we fine tune the Memorial day forecast.