My last post two weeks ago ended with the following…
If this all happens as currently forecast, the 2nd half of June could end up cooler than normal due to a NW flow, but we may not see very much in the way of precipitation.
This turned out to be a good forecast, so much so that I haven’t even had to run the A.C. for the past week. Unfortunately, the lack of recent rainfall has me somewhat concerned since there doesn’t appear to be much relief in the long range forecast.
I moved to Bowling Green in 2005 and I have yet to see a wetter than normal summer. All three summers I have experienced in south-central KY have been dry and 2008 has gotten off to a dry start. Rainfall during the three summer months (Jun – Aug) averages 13 inches, but Bowling Green has received only 9.2 inches on average the past three summers (excluding the 5″ from Katrina that occurred at the tail end of August 2005, which was dry to that point). With the SE ridge so dominant during summer the past few years, I am amazed that it ever rains here in summer.
The teleconnections point to a positive NAO, negative EPO, and positive PNA for the next 10-14 days, which largely translates to a zonal flow without much in the way of jet stream amplification. The models bear this out as the NW flow of Tuesday is replaced by a zonal flow aloft combined with a southerly flow at the surface by Wednesday. In other words, typical heat (highs around 90) and humidity (dewpoints 65-70) for this time of year.
The good news is that the return of Gulf moisture combined with the lack of a capping ridge should result in some afternoon convection across the Mid-South starting Thursday and continuing through Saturday, when a cold front sweeps across the region and brings about a brief cooldown for early next week. This system should spawn more severe weather across the Midwest, although there is a chance of severe weather across northern Kentucky during the Saturday-Sunday time period.
In the long range, both the ECMWF and GFS show that an Eastern trough should rebuild later next week. This is also supported by the GFS ensembles. Once again, this trough is too far east to bring much precipitation to KY, but it should keep temperatures below seasonable values.