087
FXUS63 KLOT 070529
AFDLOT

Area Forecast Discussion
National Weather Service Chicago/Romeoville, IL
1229 AM CDT Mon Oct 7 2024

.KEY MESSAGES...

- Dry weather continues through the week, with temperatures
  trending above average.

&&

.DISCUSSION...
Issued at 152 PM CDT Sun Oct 6 2024

Through Next Sunday:

It`s a pleasant Sunday out there today, although a bit windy and
certainly dry. Dewpoints across the area have mixed down into
the 30s with the driest conditions found south of I-80 where a
couple of sites have Tds down in the upper 20s. Temperatures
early this afternoon have made it into the lower and middle 70s
yielding RH values as low as the upper teens to around 25%.
Meanwhile, winds out of the west have been regularly gusting to
25 to 30 mph. This will continue through late afternoon before
winds start to step down through the evening. Fire weather
concerns will persist through the remainder of the afternoon; an
SPS is currently in effect CWA-wide through 23Z highlighting
the concerns.

Guidance is in agreement that temps will begin to cool off here
by mid-afternoon, a few hours earlier than we would normally
expect. This is the result of continued cold advection as a
continental polar airmass spills over the region behind a
departing storm system. Winds may take a bit longer to subside
closer to the city this evening, but winds should eventually go
light by late tonight. The combination of the light winds, clear
skies, and cold advection will provide us with some awfully
chilly conditions overnight into early tomorrow, at least
relative to what we`ve seen lately. Overnight lows are forecast
in the lower and middle 40s for most while areas around the city
could stay up near 50. Upper 30s are expected west and
northwest of the Fox Valley to out near Rockford with a couple
of spots possibly tapping middle 30s. At least patches of frost
are likely across rural, open areas out this way late tonight
and early tomorrow morning with more developed areas less likely
to see any frost. Given the low coverage expected, opted out of
issuing a frost headline for tonight.

Meanwhile, a sizable upper ridge is in the process of building
over SW Canada as some stronger upper flow moves onshore the
PNW and BC coasts. Finding ourselves on the leeward side of this
developing ridge, surface high pressure will advect in from the
central Plains and overspread the Midwest during the day
tomorrow. Tomorrow looks to be the coldest day in the forecast
period with highs progged in the lower and middle 60s. As the
ridge propagates eastward we should see a steady warmup with
highs climbing through the 70s during the middle of the week.
The ridge will center itself north of the Midwest late this
week, losing some amplitude as it does. Nonetheless, this should
help late week temperatures get back into the lower 80s!
Conditions will remain quiet and rain-free this week as the high
steers any weather away from the region. Medium range guidance
is in solid agreement on the ridge giving out over the weekend
and a wave moving into the region from the northwest late
Saturday into Sunday. Some models want to produce a bit of rain
with this. It looks like we might still be a bit dry to support
much in the way of rain, but this does appear to be the best
precip potential over the next week.

Doom

&&

.AVIATION /06Z TAFS THROUGH 12Z TUESDAY/...
Issued at 1229 AM CDT Mon Oct 7 2024

No major forecast concerns are expected at the terminals
through the TAF period as high pressure will be building
overhead. Winds tonight will generally remain light with speeds
in the 5 to 7 kt range and directions out of the northwest.
Though, a few gusts in excess of 18 kts look to persist for the
next couple of hours at GYY. For Monday, winds will become more
west-northwesterly through the day with speeds generally in the
8 to 10 kt range but occasional gusts in the 15 to 18 kt range
may occur at times. Otherwise, mostly to completely clear skies
are expected through the period.

Yack

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...None.
IN...None.
LM...Small Craft Advisory until 7 AM CDT this morning for the IL
     nearshore waters.

     Small Craft Advisory until 10 AM CDT this morning for Calumet
     Harbor to Gary IN.

     Small Craft Advisory until 4 PM CDT this afternoon for Gary to
     Burns Harbor IN-Burns Harbor to Michigan City IN.

&&

$$

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