261
FXUS63 KLOT 151919
AFDLOT

Area Forecast Discussion
National Weather Service Chicago/Romeoville, IL
219 PM CDT Sun Sep 15 2024

.KEY MESSAGES...

- Dry and summer-like conditions will persist through the end of
  the week and possibly into next weekend.

&&

.DISCUSSION...
Issued at 219 PM CDT Sun Sep 15 2024

Tonight through Saturday...

A broad dome of high pressure will continue to reside over the
Great Lakes through the upcoming week which should keep any
moisture from the Gulf of Mexico trapped well south of our area
across the Tennessee Valley and Deep South. Therefore, our
stretch of dry and summer-like conditions will continue through
the week with daily highs generally in the mid-80s and overnight
lows in the mid-50s to lower 60s. Though, slightly warmer
conditions are possible on Monday and Tuesday as the
aforementioned high drifts westward across lower Michigan
resulting in less cirrus clouds and temperatures flirting with
the upper 80s to around 90.

Additionally, the unabated sun and warmer temperatures should
also yield deeper diurnal mixing Monday and Tuesday creating
lower afternoon dew points and humidity. While winds during this
period will remain light, minimum RH values are forecast to dip
into the 20 to 25 percent range (especially across our eastern
CWA) which could lead to a heightened concern for grass and
brush fire starts. Afternoon RH values are expected to increase
on Wednesday as high- level cloud cover and modest low-level
moisture increase due to a tropical system impacting the Mid-
Atlantic.

Heading into next weekend, guidance continues to show a broad
trough developing across the western CONUS and tracking into the
central Plains. While this should aid in breaking down the
ridge over the Great Lakes, moisture return ahead of the trough
looks rather weak and may not be sufficient to produce any
meaningful rainfall in northern IL or northwest IN. That said,
have decided to maintain the slight chance POPs (around 20%)
offered by the NBM next weekend, but suspect many areas could
remain dry and thus see worsening drought conditions heading
into next week.

Yack

&&

.AVIATION /18Z TAFS THROUGH 00Z TUESDAY/...
Issued at 1216 PM CDT Sun Sep 15 2024

Cirrus and sparse high-based cumulus will continue through
Monday. SE winds 5-10 knots will prevail except for a lake-
enhanced shift E each afternoon at the Chicago metro sites.

Kluber

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...None.
IN...None.
LM...None.

&&

$$

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