Area Forecast Discussion
Issued by NWS Milwaukee/Sullivan, WI
FXUS63 KMKX 300827
Area Forecast Discussion
National Weather Service Milwaukee/Sullivan WI
327 AM CDT FRI SEP 30 2016
.TODAY AND TONIGHT...Discussion Coming Soon...
.SATURDAY THROUGH SUNDAY NIGHT...Forecast Confidence Is Medium.
Models continue to show the closed 500 mb low shifting slowly
northward across northern Indiana Saturday, before moving into
southeast lower Michigan Saturday night. The closed low then
slides off to the east Sunday and Sunday night. There is a little
variation among the models with the exact 500 mb low track.
Several 500 mb vorticity maxima, with differential cyclonic
vorticity advection, should combine with decent column moisture to
result in a good shot at rain showers Saturday morning in the
eastern counties. This does continue into the afternoon. May need
to raise PoPs more for Saturday across the area, if the wet look
of the models continues.
There is some drying in the air column Saturday afternoon, which
may limit the areal coverage of any showers. Did not add thunder
for Saturday afternoon and evening in the far southeast counties,
as mean layer CAPE values are quite low.
Kept PoPs mainly in the eastern counties Saturday night into
Sunday morning, as the 500 mb low starts to push east of the area.
Weak high pressure should bring quiet weather for Sunday afternoon
and night, with drier air working into the area. Highs should
remain near seasonal normals, with mild lows.
.MONDAY THROUGH THURSDAY...Forecast Confidence Is Medium.
Dry southeasterly flow Monday into Tuesday night should bring a
period of quiet weather to the area. Temperatures may rise a bit
during this time, reaching the lower 70s inland on Tuesday.
Onshore winds should keep the coolest temperatures near the lake.
The next system should then move east into the region Wednesday
into Thursday. A fairly strong cold front is shown by the
ECMWF/GFS to move east into the region Wednesday night, exiting on
Thursday. This is accompanied by broad cyclonic flow at 500 mb, as
a deep 500 mb low remains over far northern Minnesota.
Area forecast soundings show rather weak instability Wednesday
afternoon and evening across the area. For now, will continue to
mention PoPs for showers and slight chances for thunderstorms
for Wednesday into Wednesday night, with showers lingering
Thursday. The mild temperatures should remain across the area.
.AVIATION/12Z TAFS/...Discussion Coming Soon...
.MARINE...Discussion Coming Soon...
LM...SMALL CRAFT ADVISORY until 4 AM CDT Saturday for LMZ643>646.
TODAY/TONIGHT AND AVIATION/MARINE...Gehring
Saturday THROUGH Thursday...Wood