Area Forecast Discussion
Issued by NWS Northern Indiana

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966
FXUS63 KIWX 191819
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
219 PM EDT Thu Sep 19 2024

.KEY MESSAGES...

- Drought conditions will continue to worsen across the area
  with the best chance, albeit low confidence, coming Sunday
  night into Monday chances for much needed rainfall.

- Above normal temperatures will persist a few more days,
  before cooling somewhat into next week.

&&

.DISCUSSION...
Issued at 218 PM EDT Thu Sep 19 2024

Region continues to be dominated by high pressure to the east that
will have little in terms of dynamics to displace it until early
next week. A weak cold front will edge east over the next 24 to 36
hours, slowly washing out over time as it becomes orphaned from the
better overall flow and dynamics. Dewpoints ahead of the front are
in the mid 60s, with these attempting to make a run at the area, but
are likely to be mixed out somewhat given the antecedant dry
conditions and shallow nature of the moisture (as depicted by 12Z
KILX and KDVN soundings). While upper level flow isn`t horrible and
DCAPES AOA 1000 J/KG will exist courtesy of the EML, low level
instability will be very limited resulting in some cu development
tomorrow afternoon along with an outside chance of a few cells
gaining some height, but struggling to organize in any fashion. In
addition, upstream convection may leave cloud cover around in the
morning to limit heating. Marginal risk was introduced earlier for a
portion of the area, mainly for the "pulse" nature of any storms
that somehow can get some development. While possibly overdone,
previous shift layout of pops in the NW Fri afternoon isn`t
unreasonable at this point pending impacts from upstream convection.
Will make a few minor tweaks but overall leave alone. Did remove
slight chc pops Fri evening as any activity that forms should
quickly diminish around 00Z Sat.

Above normal temperatures (well into the 80s) will persist into
Saturday, with some locally cooler temps possible tomorrow if cloud
cover or precip coverage is more than currently forecasted. Upper
low currently located off the SW California coast, will move slowly
ENE over the weekend, reaching Iowa by 12Z Mon. Somewhat better
moisture influx will accompany this to bring hopefully improved
chances for showers and storms as early as Sunday night, possibly
lingering into Tuesday as northern stream wave drops in and lingers
into Wednesday. Confidence remains low on specific details including
timing and how widespread the precip may be. Model blends continue
to bring in likely pops and this is climatologically and logically
unreasonable at this point. Have limited pops as best I can while
remaining collaborated with surrounding offices. Cooler temperatures
will arrive starting Sunday with highs by the middle of next week in
the low to mid 70s. It should be stated that even with the chances
for rainfall Sun-Tue, overall drought conditions will remain
unchanged, if not worsen for many areas as amounts won`t be enough
to remove the deficits in place.

Last, but not least, as noted by the overnight forecaster, trend
towards drier conditions should occur behind the upper low as it
shifts far enough east late Wed into Thu.

&&

.AVIATION /12Z TAFS THROUGH 12Z FRIDAY/...
Issued at 1144 AM EDT Thu Sep 19 2024

VFR through the period. Low level moist axis extending
downstream of lake Erie into ern IN yielded another round of
dense fog overnight but expected to mix out this aftn and
dissipate as flow veers srly into Fri morning. Thus do not
expect a repeat of dense fog invof KFWA.

Otherwise weak frontal zone will push across the terminals late
Fri aftn with an uptick in mid lvl based cloud cover expected.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...Air Quality Alert until midnight EDT /11 PM CDT/ Friday night
     for INZ005-012>015-022-023-104-116-204-216.
     Air Quality Alert until 11 PM CDT this evening for INZ103-203.
OH...None.
MI...None.
MARINE...None.

&&

$$

DISCUSSION...Fisher
AVIATION...T