Fall Cool Down is Here

Currently: Ridging has been persistent over the eastern portion of the contiguous US for quite some time now with little variations in the jet stream pattern as a whole. As a result, heat and high humidity have been seemingly relentless over the past several weeks across the Ohio Valley. However, this trend is starting to break down, as we would typically expect this time of year as we now have more nighttime than daytime hours in the Northern Hemisphere. Resultantly, the thermal distribution begins to shift southward towards the equator, and the jet stream responds accordingly with a similar shift south with more prominent Rossby wave activity.

Nonetheless, lets look at our setup for this upcoming week. These are images of good news for us as relief from the persistent heat is arriving:

500 hPa wind speeds and isoheights indicate ridge over Ohio Valley at 00 Z Monday

500 hPa wind speeds and isoheights indicate a ridge over Ohio Valley at 00 Z Monday

NAMUS_sfc_thetae_012

Surface Theta-E and 10 m wind vectors show clear boundary between warm/humid airmass and cooler/dryer airmass to NW at 00 Z Monday

Monday: With approaching cold front to the NW late Sunday, it is expected to arrive in the overnight hours and morning commute time period of Monday the 26th. This is particularly good news as daytime highs will dip into the low 70’s for Bowling Green and the surrounding region, rather than the lower 90’s as we’ve been experiencing lately. Light rain is possible with the passage of the front as well but should taper off throughout the day.

Trough axis and NWerly winds at 500 hPa will usher in relief for days to come. Image Valid for 00 Z Tuseday.

Trough axis and WNW winds at 500 hPa will usher in relief for days to come. Image valid for 00 Z Tuesday.

This week: Guidance suggests this cooler/dryer airmass will stick around for awhile with daily high temps expected to stay in the 70’s throughout the upcoming week.┬áThis is likely as it appears the upper-level low is expected to detach from the primary branch of the polar jet and allow for NW winds in the upper levels to dominate our stable and dryer weather pattern for the days to come.

In short, expect fair skies with highs in the low to mid 70’s for the week. Lows near 50 every night and similar dewpoints throughout the week in the low 50’s. Oh so nice! Seasonal fall weather is here and we all hope it stays for awhile!

This entry was posted in Kentucky Weather, U.S. Weather. Bookmark the permalink.