SEPTEMBER'S FINEST...
The last couple days have been spectacular from a weather standpoint. You all know what I mean so sense going into the details. Now of course, we are entering September, the start of Meteorological fall which ends the last day of November. Fall or not, we are going to pull another rabbit out of the hat today with a special start to September that includes all the makings of a fine summery day. Thank you sir, I'll take another!
About the only change Thursday will be a period of clouds in the morning as warm advection develops on return flow and southerly winds. These clouds could spit out a few sprinkles but they should be fast movers and we get back to mostly sunny skies in the afternoon. Temperatures will end up warm in the mid 80s but humidity will be tolerable and winds light. Nothing to complain about.
Friday things get a little more complex as moisture increases ahead of a cold front. Temperatures might reach the upper 80s, especially in the far south. That combined with dew points in the mid to upper 60s will make things a bit more uncomfortable. It will also lead to a low chance of isolated showers and storms. Coverage looks minimal and amounts light. Most areas stay dry. Here's the composite radar showing the spotty nature of the showers.
Friday night and Saturday the front will impinge on the instability and models do show enough forcing for at least widely scattered showers and a few storms. The latest guidance keeps most of the threat (minimal as it is) confined to Saturday as the front has slowed from previous expectations. Beyond that, models have gone a bit rogue today showing the potential for some showers even into Sunday and Monday. This is tied to a weak upper level low in Missouri. Confidence in this solution producing much in the way of rain is low. My expectation currently is that little if any rain falls Sunday and Monday and where it does coverage is isolated, brief, and most likely light. If you have outdoor plans there should be lots of dry hours, assuming a shower pops up (which is still not a certainty.) This part of the forecast will need to be monitored to see how trends unfold in the next 24 hours. For now, here is what models are suggesting for rainfall totals through Labor Day.
The NBM (national model blend)
WPC (Weather Prediction Center)
the GFS
The EURO
As far as temperatures the whole holiday weekend (Saturday through Monday will be mild). Saturday currently looks the warmest with highs low to mid 80s. Sunday and Monday should have passing clouds which could keep things more in the range of the upper 70s to low 80s...which is seasonal.
From the looks of the long range guidance the next 10 days have a warm appearance. Throughout the northern half of the nation readings are expected to average near to well above normal over the period ending September 10th.
Then there is something I'm watching tied to super typhoon Hinnamnor. As you can see over the next 6 days the storm is expected to travel near or just west of Japan as it heads into the north Pacific. About this time every year I watch this area for the correlation that similar tracks ultimately develop a downstream trough over the U.S. within 10 days. Such a trough can tug significantly colder air into the long wave pattern
As of today the EURO has that cool look with the EPS control showing a strong upper air low in SC Canada with a deep trough extending into the Midwest. This begins to take shape around September 10th.
Whether this happens, (especially to this degree) remains to be seen. However, it it does you can see the chill it brings with temperature departures 12 to 15 degrees below normal Monday the 12th.
Highs that day are confined to the upper 50s from NE Iowa into the upper Midwest,
This will be an interesting trend to keep and eye on in coming days. Actually, I've had my eye on this period for some type of cool-down for the past several days. This is more than I was expecting. Time will tell.
With that, I am signing off. Have an outstanding day and as I always say, roll weather...TS
