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Area forecast discussion...updated 
National Weather Service Milwaukee/Sullivan WI
1145 am CDT Tuesday Sep 23 2014


High pressure to the east of the region will continue to bring
quiet weather to the area this afternoon. Sunny skies are
expected...with highs reaching the lower to middle 70s away from
Lake Michigan. Onshore winds by early this afternoon will limit
highs to around 70 near the lake...before falling into the 60s
during the rest of the afternoon.


Aviation/18z tafs/...

VFR conditions are expected this afternoon...tonight and Wednesday
across taf sites. High pressure to the east of the region will
bring quiet weather to the area. May see ground fog in low lying
areas and river valleys...but taf sites should remain fog Free.

Lake breeze will turn winds southeast this afternoon at the
eastern sites...with south winds at Madison. Winds will remain
south to southeast tonight into Wednesday at taf sites...becoming
southeast Wednesday afternoon.


Previous discussion... /issued 321 am CDT Tuesday Sep 23 2014/

Today and tonight...forecast confidence...high

An upper ridge will move across WI today with surface high pressure
slowly moving to the east. A lake breeze will develop for the
afternoon given the light synoptic flow. 925 mb temperatures around 14-15c
and MOS guidance supports highs in the lower 70s but slightly cooler
near the lake. The upper ridge axis will slide to the east tonight as
the upper trough over the Great Plains moves into western Minnesota and northwest Iowa
by 12z Wednesday. Southerly flow will increase tonight just above the surface and this
should result in milder temperatures and limit the fog to only low lying

Wednesday and Thursday - confidence...medium
upper trough slowly approaches from the eastern Dakotas towards far
western WI by days end. Area of cyclonic vorticity advection
associated with this feature affects locales from extreme SW into
NC WI largely bypassing the County Warning Area. Meanwhile in the lower levels a
very dry regime with lingering influence of slowly departing
surface high. Surface/850 flow remains anticyclonic. BUFKIT
soundings show some moistening at or above 12k feet with the rest of the
column parched. 850 low level jet remains west and then diminishes Wednesday
night into Thursday. Airmass remains dry. Upper low gradually
drops south from SW WI. However surface/850 highs show even
greater influence with a westward push. European model (ecmwf) shows light precipitation
in western County Warning Area though dry airmass..influence of lower level
anticyclonic flow and low guidance probability of precipitation suggest keeping spirit of
going dry forecast intact.

Friday through Monday - confidence...high
broad upper low shifts further southwest with elongated ridging
becoming dominant feature. Surface ridging also looks to keep
things dry this period. GFS a bit more progressive on returning
the upper low for Sunday and Monday while trends in the European model (ecmwf) keep
the circulation further southwest with upper and lower level
anticyclonic flow persisting. Even with the GFS showing more
progression the dry low levels and the persistent hold of the
surface high will likely keep the dry scenario going.

Aviation/12z tafs/...light ground fog will occur intermittently
through sunrise at kmsn and possibly well as in low lying
areas. Otherwise MO clear skies and VFR conditions will prevail
today and tonight. Any ground fog tonight will only be in low lying areas
with VFR conditions at the taf sites.


Mkx watches/warnings/advisories...


today/tonight and aviation/marine...collar
Wednesday through Monday...gehring

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