Area Forecast Discussion
Issued by NWS Milwaukee/Sullivan, WI
FXUS63 KMKX 202127
Area Forecast Discussion
National Weather Service Milwaukee/Sullivan WI
327 PM CST Mon Feb 20 2017
TONIGHT - Confidence...Medium
Water vapor animation shows the northward moisture transport from
the southern Plains ahead of the mid level trough axis. The surface
low and front is pushing towards the western Great Lakes helping to
draw the higher dew points...50 plus readings into srn WI. Meso
models show gradual west/east translation of shra/isold tsra through
the night. Since elevated instability continues to be noted on
Bufkit soundings, will retain the mention of thunder. Temps will be
unseasonably mild with lows likely not dropping out of the 50s for
most areas, which makes these values some 20 plus degrees above the
normal high temps.
.TUESDAY - Confidence...Medium
Low level frontal forcing and influence of mid level wave shift east
early with a period of mid level ridging and dry westerly flow. This
will result in clearing skies and warm temperatures. 925 temps will
reach the 9-11c range which support temps back into the unseasonably
warm 60s. The GFS soundings seem to have a better handle on the
depth of mixing than the NAM so leaned in the direction of the
former which is reflected by the MOS numbers as well.
Tuesday night through Thursday...Forecast confidence high.
Sswly winds will prevail Tue night into Wed evening as a couple
shortwave troughs move ewd across the nrn USA and srn Canada. Low
pressure associated with the 2nd shortwave trough will track from
ern SD to ne WI on Wed bringing the strongest surge of warm air
of the season. 925 mb temps of 13-15C and sunshine should yield
record high temps in the upper 60s to lower 70s. The trailing cold
front will then pass Wed night bringing nely winds for Thu
although temps will still be above normal in the 40s and 50s.
There are small chances of rain late as mid level warm advection
begins ahead of cyclogenesis over KS or OK.
.LONG TERM...Thursday night through Monday...Forecast confidence
Strong low pressure will track from KS to across se WI through
Fri evening. Widespread precipitation is expected Thu night
through Fri night with light snow lingering on Sat. 1.00-1.50
inches of liquid is currently forecast and will fall mostly as
rain although some snow accumulation is expected, especially
toward central WI. More seasonal temps will then prevail with a
polar high passing on Sun. A low pressure area may bring rain and
snow chances for Mon but much uncertainty with the track and
.AVIATION/00Z TAFS/...Mid/high level cloud cover continues
to thicken up. Cigs lower with precip advancement from wrn WI. As
surface front and mid level energy arrive tonight the threat for IFR
cigs/vsbys and rain will be on the increase. Although it looks like
things will be on the move as LLVL RH progs dry things out pretty
quick after 12z Tuesday.
.MARINE...A Small Craft Advisory is in effect until 3 AM Tue. Breezy
sely winds will continue through the evening ahead of an approaching
frontal boundary. The sely winds will build high waves especially
north of Port Washington. The winds will then turn swly Tue AM along
with a reduction in wave heights. The sly winds will also bring
moist air over the relatively cold waters of Lake MI resulting in
areas of fog, possibly becoming dense. The fog threat is greatest
Another record high today for Madison. Record highs are forecast
for Tue-Wed at Milwaukee and Madison.
Milwaukee record highs: 2/21 = 58 (1930), 2/22 = 62 (1984).
Madison record highs: 2/21 = 60 (1930), 2/22 = 60 (1984, 1930).
LM...Small Craft Advisory until 3 AM CST Tuesday for LMZ643>646.
TONIGHT/Tuesday AND AVIATION/MARINE...Collar
Tuesday NIGHT THROUGH Monday...Gehring