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Area forecast discussion 
National Weather Service Green Bay WI
528 PM CST Tuesday Jan 27 2015

Updated aviation portion for 00z taf issuance

Short term...tonight and Wednesday
issued at 258 PM CST Tuesday Jan 27 2015

The latest rap analysis and satellite/radar imagery show Arctic high
pressure nosing southwest across the Upper Peninsula and the state
of Wisconsin. But despite the ridge axis sharpening over NE
Wisconsin...low stratus has been awfully difficult to erode this
afternoon. Clouds over Northern Lake Michigan are very slowly
eroding from east to west...and as boundary layer flow lightens and
backs to the north later this afternoon...think this will accelerate
clearing over the Fox Valley and Lakeshore. Otherwise...overcast
conditions to remain over central and north-central Wisconsin.
Looking upstream...clouds are increasing again over the northern
plains and Northwest Lake Superior ahead of the next clipper system
which will arrive Wednesday night. In the and temperature
trends are the main forecast concerns.

Tonight...Arctic high pressure will temporarily build across eastern
Wisconsin this evening then retreat back east overnight. Still
anticipating at least partial clearing taking place over the Fox
Valley and Lake Shore as the ridge axis moves into that area. Farther
west...winds will turn to the south or southwest...and trends over
the u.P. Support that clouds will just rotate northward...leaving a
low overcast deck in place. As a result...increased sky cover.
Then overnight...middle and high clouds will be returning from the
northwest...and any clearing over eastern Wisconsin should go back
to broken or overcast. Trended warmer with low temperatures due to the
persistent cloud cover.

Wednesday...low pressure will be moving into the northern
Mississippi Valley during the afternoon. As winds back to the
southeast...warmer low level air will finally surge into central and
northeast Wisconsin...which should erode any remaining low overcast.
However...will still have ample middle and upper clouds
overhead...making for a mostly cloudy day. An 850mb warm front will
be making into north-central and central Wisconsin by late in the
afternoon...but prognosticated soundings continue to show a wedge of dry
air around 10kft that should be enough to keep the area dry. Highs
warming into the low to middle 30s.

Long term...Wednesday night through Tuesday
issued at 258 PM CST Tuesday Jan 27 2015

Northwest upper flow will continue through the it will
be generally cold and dry. There are at least two opportunities for
some snow. The first is tomorrow night and early Thursday as jet
energy approaches from the west. There isn/T much moisture
available until the system gets east of Wisconsin. Therefore snow
should be light and might begin as sleet across the central and
east central areas. There is another chance of snow Saturday night
and Sunday ahead of Arctic air. The GFS and European model (ecmwf) have a few waves
of low pressure that move northeast along the front...resulting in
lots of differences in timing and snow amounts. Mild Pacific air
will bring US warmer than normal temperatures Thursday then below
normal temperatures are expected through the middle of next week.
There. Wind chill advisories may be needed Monday.

Aviation...for 00z taf issuance
issued at 526 PM CST Tuesday Jan 27 2015

Looks like we/ve missed out on our opportunity to get rid of the
low clouds. They are now firmly in place across the entire forecast
area...trapped by the weak flow within the low-level ridge. Expect
ceilings and visibilities to gradually come down overnight...with improvement
not occurring until middle-day or afternoon tomorrow.

Grb watches/warnings/advisories...


Short term.....Mpc
long term......rdm

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