IWX issues Area Forecast Discussion (AFD) at Sep 28, 12:03 PM EDT
309
FXUS63 KIWX 281603
AFDIWX
Area Forecast Discussion
National Weather Service Northern Indiana
1203 PM EDT Sun Sep 28 2025
.KEY MESSAGES...
- Dry and mostly sunny into mid week next week.
- Highs will be in the 80s through Tuesday cooling into the 70s
for the middle and latter portions of the work week.
&&
.DISCUSSION...
Issued at 304 AM EDT Sun Sep 28 2025
With the tropical systems off the southeast shore of the CONUS, the
weather pattern becomes stalled out with a rex (N-S) or omega
(bookended by the oceans) block overhead. A ridge of high
pressure become entrenched overhead from today into at least
next weekend and this will help to restrict the formation of any
system potentially providing rain. Closer to the surface, a
cold front approaches, today, from the northwest, but is slowed
up and stalls out overhead. Normally, a cold front swinging
through on a mostly clear day this time of year might bring some
increased winds, but the gradient is weak this time since it
stalls out so only a weak LLJ exists and so winds are expected
to stay relatively weak. A well mixed boundary layer to 800 mb
where a temperature around 10C resides allows for a max temp in
the 80s. Pooling of moisture out in front of the boundary brings
60 degree dew points into the antecedant airmass of 50 degree
dew points. These conditions together allow for another pleasant
day. One wrinkle in this is that, there could be some uptick in
winds and downtick in dew points in areas south of US-24 where
mixing dries out the atmospheric column further.
Underneath the stalled, dry pattern for this week, surface high
pressure that rides overtop the aforementioned ridge and ends up in
southeast Canada mid to late week this week. This high pressure
system pushes a drier (dew point-wise) and slightly cooler airmass
into the Great Lakes behind a backdoor cold front. As a result,
we'll go from the 50s and 60s in dew points today to down into the
40s by the end of the week and from the 80s for highs today down
into the 70s by the end of the week. Thursday has some upper 20
percent MinRH values already forecast, which is significant because
normally that's a value it struggles to forecast. The good thing is
winds are still weak during this period so that'll help keep any
grass fires that start from spreading too much. Low temps go from
the 50s down into the 40s. Given how long this period of dry air is,
wouldn't be surprised if this ridge lingers longer than models have
it so that the next trough doesn't arrive until next week some
time.
&&
.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 1203 PM EDT Sun Sep 28 2025
Upper ridging will continue to promote mainly clear skies, light
winds and VFR conditions through the TAF cycle and beyond.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...None.
OH...None.
MI...None.
MARINE...None.
&&
$$
DISCUSSION...Roller
AVIATION...Steinwedel
Source: IWX issues Area Forecast Discussion (AFD) at Sep 28, 12:03 PM EDT (https://mesonet.agron.iastate.edu/p.php?pid=202509281603-KIWX-FXUS63-AFDIWX)
---------------
If I'm using your data in a way that is against your terms please email the team at "threatweb@pupswoof117.com"! I am a bot who will not respond in the comments at all and is only designed to post RSS feeds!