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fxus63 kiwx 181052 

Area forecast discussion
National Weather Service northern Indiana
652 am EDT Wed Sep 18 2019

issued at 338 am EDT Wed Sep 18 2019

Areas of ground fog early will lift after sunrise yielding a mostly
sunny sky with highs from around 80 to the mid 80s. The warm weather
will persist into the weekend with highs in the 80s each day.
Chances for showers and storms will increase this weekend with
the best storm chances from Saturday night into early Monday. Heavy
rainfall is possible during this time.


Short term...(today through friday)
issued at 338 am EDT Wed Sep 18 2019

Crossover temperatures from yesterday and ongoing hydrolapse
(humidity profiles) suggest reasonable chances for fog formation
early this morning. However, 24 hours dew point changes indicate
somewhat drier air has spread across the area from the northeast
since yesterday morning. Less fog was observed at this time
compared to yesterday. All considered, will keep the mention of
patchy fog early. The fog will mix out rapidly after sunrise with
skies becoming sunny.

Although waning insolation with fast approaching traditional
autumnal beginning on Monday, very warm 850 mb temps close to 18c
along with reasonable mixing will allow temperatures to climb into
the low to mid 80s today. Have rejected GFS thermal profiles
given favored European model (ecmwf) strength of upper level ridge building north
of the Ohio (in the light of poor recent performance with a
pronounced cool bias with a number of events of this type of
pattern). In this regard, have been perpetually raising the
blended model highs from today through Friday to come in line with
the European model (ecmwf) with appears to have the best handle on the pattern.
The European model (ecmwf) 30 degree diurnal rises at a number of sites Thursday
appear on track and is favored this package. Have kept Friday dry
also favoring the European model (ecmwf). It appears the GFS is generating
convective feedback (developing storms too close to the upper
level ridge in a area of large scale subsidence).


Long term...(friday night through tuesday)
issued at 338 am EDT Wed Sep 18 2019

An active pattern is ahead this weekend as a major shortwave trof
ejects northeast into the Midwest and ingests a tropical system
along the Gulf Coast that was near Houston early this morning.
Ahead of this upper level system, precipitable water values were
already above records including a 1.67 inch observation at
International Falls. Favor the European model (ecmwf) timing with heavy
precipitation possible from late Sunday through early Monday with
precipitable water values straddling 2.0 inches. Temperatures
will still be warm Saturday (in the 80s), but cool into the 70s
Sunday through Tuesday.


Aviation...(for the 12z tafs through 12z Thursday morning)
issued at 619 am EDT Wed Sep 18 2019

High pressure situated over northern Indiana will result in VFR
conditions and light south-southeast winds for the duration of the 12z taf
cycle. Fog has stayed outside of the terminals throughout the
overnight hours, and should quickly dissipate after the 12z. For
this reason will remove tempo mention from kfwa.


Iwx watches/warnings/advisories...


short term...skipper
long term...skipper

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