Enjoy the comfortable weather while its here cause it’s not going to be around much longer!
Thursday and Friday will still be fairly comfortable with slowly increasing humidity but highs in the mid to upper 80s.
What we have though is a developing Bermuda High , a very common term used along the east coast during the summer time. Its an area of high pressure or a ridge which sets up between the SE US and the island of Bermuda, the clockwise flow around high pressure leaves the east coast on the western side of the high, and that means a flow from the South and Southwest up the east coast directly from the tropics and the Gulf of Mexico. You were warned last week about this potential heat wave!!
This set up transports a hot and humid air mass from the SW (Gulf of Mexico and drives it NE right into the forecast area, these set ups are notorious and most known for VERY HIGH HUMIDITY. With a flow usually out of the south and high humidity, extremely high temperatures (upper 90s and 100s like we saw last week) are not too common with this set up , due to so much moisture in the air , but the humidity will make it feel very hot regardless. Again this is a very common set up for the east coast over the summer time so it’s really nothing out of the ordinary but this one could be long-lasting.
By Saturday you can see the high pressure over the western Atlantic transporting a Southwest flow up the east coast and a hot and very humid air mass moving in
Mid week next week, the same set up is in place with the Bermuda high holding strong and the same southwesterly wind with hot and humid condition
So all in all, we can expect widespread upper 80s to low 90s starting (mid to upper 80s along the coast and higher elevations, low 90s elsewhere) Saturday and lasting through much of next week with dew points in the upper 60s to mid 70s and that will be VERY uncomfortable with heat indexes in the upper 90s to lower 100s.
One thing we have to watch for is the chance of isolated to scattered storms each afternoon with the hot humid air mass in place along with some pesky disturbances, any storms will be very slow-moving so if you get caught under one , flash flooding could be a concern as there will be light upper level winds so therefore no real steering current for storms,
This whole pattern is driven by cold stratospheric conditions over the middle latitudes, the coldest anomalies are over the United States and thus the reason why the US has been very hot this summer so far , in balance to a cold stratosphere the surface is forced to warm and thus the reason why we have had heat ridges and lots of warmth since the end of 2011.
Signs of Relief In The Long Range
We have established that the cold stratosphere is the main driver behind heat, but we are starting to see stratospheric WARMING , and we can tell because the heat ridge that plagued the country last week is slowly dying, and with that being said while I expect the rest of July overall to be on the hot and humid side and the month to be above to well above normal , I am watching and expecting this whole hot pattern to break down slowly as we go into August and I think August will bring some much-needed relief as not only d we have stratospheric warming, but a developing El Nino , the effects will be determined on the general orientation but El Nino enhances chances of more troughs and thus cooler weather in the east, and that’s what I will be watching for , more on that in the coming weeks though!