Area Forecast Discussion
Issued by NWS Milwaukee/Sullivan, WI
FXUS63 KMKX 220234
Area Forecast Discussion
National Weather Service Milwaukee/Sullivan WI
934 PM CDT Fri Apr 21 2017
.MARINE...Light winds and low wave heights will prevail from
tonight into Sun.
.PREV DISCUSSION... (Issued 653 PM CDT Fri Apr 21 2017)
UPDATE...Srn WI will remain on the srn periphery of cirrus
clouds tnt into Sat AM as an upper trough tracks from the central
Great Plains to the Middle MS River Valley. The cirrus will
decrease on Sat as winds aloft become more nwly. The clouds and
some wind flow should prevent widespread frost for early Sat AM.
Otherwise, a w-e sfc ridge will settle over srn WI from the north
for Sat-Sat nt.
AVIATION(00Z TAFS)...VFR conditions tonight into Sun.
PREV DISCUSSION... (Issued 252 PM CDT Fri Apr 21 2017)
TONIGHT AND SATURDAY...Forecast Confidence is High...
The midlevel trough will depart the region this evening. Then
drier air will move in as a broad area of high pressure moves
into northern WI overnight and remains in place through Saturday.
Skies will be mostly clear with light northeast winds. This will
allow temperatures to drop to the lower to mid 30s tonight with
some frost possible. Some vegetation is growing and we are getting
into our median first frost time frame, especially across the
south. Temperatures will warm into the middle and upper 50s on
Saturday, with cooler readings near the lake.
Saturday night through Monday...Forecast confidence is high:
High pressure will remain in place for the rest of the weekend
into early next week, bringing plenty of sunshine and mainly above
normal temperatures. It will be cooler near Lake Michigan through
this period due to onshore winds. Could see a fairly strong push
of cooler air inland on Sunday per the NAM and ECMWF solutions.
Tuesday through Friday...Forecast confidence is medium:
The pattern is expected to become active again Tuesday through
late week as multiple low pressure systems move through the
region. Models are in decent agreement in targeting Tuesday,
Thursday, and Friday as the best chance for showers. Seeing some
instability Tuesday and again late in the week, but would like to
see better model agreement before putting thunder in the forecast.
Temps should be a few degrees above normal Tuesday under south to
southwest winds. There is the then increasing confidence in
cooler conditions for mid week. Nudged forecast highs down a few
degrees Wed/Thu. Didn`t go as cool as some models are suggesting
quite yet due to a little uncertainty, but looked like trending
things that direction was definitely needed. Does look like milder
temps will return late in the week, though pretty big differences
between ECMWF and GFS on how quick the warm temps advect back into
the region. ECMWF suggests Fri highs in the 50s to near 60, while
the GFS 925 mb temps would result in high temps closer to 80.
Cloud bases will continue to rise and become few to scattered
later this afternoon. Aside from areas of high clouds, mostly
clear skies are expected tonight and Saturday. Northeast winds
will prevail through Saturday.
Northeast winds will diminish later this afternoon. Light
northeast winds will prevail through Saturday.
Tonight/Saturday and Aviation/Marine...Marquardt
Saturday Night through Friday...DDV