Area Forecast Discussion
Issued by NWS Milwaukee/Sullivan, WI
FXUS63 KMKX 171600
Area Forecast Discussion
National Weather Service Milwaukee/Sullivan WI
1000 AM CST Fri Feb 17 2017
.AVIATION/18Z TAFS/...Still looking like only concern over the
next 24 hours or so will be potential for LLWS tonight. Progs
still show a wsw LLJ arriving which given decoupling this evening
will set up the shear scenario. All in all soundings are bone dry
with mid level ridging dominating.
.MARINE...Southerly winds today and westerly winds Saturday will
generally range from 5 to 15 knots, with a few gusts to 20 knots
at times. Quiet conditions will persist into early next week.
.PREV DISCUSSION... /Issued 325 AM CST Fri Feb 17 2017/
SATURDAY AND SUNDAY...Forecast confidence is high.
A shortwave trough will steadily lose amplitude while progressing
across the upper Great Lakes/southern Ontario on Saturday. The upper
wave will escort a surface low tracking through southern Canada,
with an associated weak cold front swinging through our area
Saturday morning. No precipitation will occur with the frontal
passage. Northwest flow and some weak cold advection could keep
afternoon highs a few degrees cooler than on Friday, but still
expect readings well above normal, with record highs potentially
within reach for some locations.
Mid-level heights will rise behind the departing wave on Sunday.
This will support weak surface ridging over the area, as Rockies
lee cyclogeneis commences to our west ahead of a high amplitude
trough. Southeasterly flow will develop during the afternoon and
persist into the evening as a warm front associated with the
surface low lifts northeast through southern Wisconsin. Mid to
high level clouds should increase through the day in association
with the warm front. High temperatures will be on the order of 20
degrees above seasonal averages, with readings in most locations
well into the 50s to perhaps 60s. The exception will be in the
Lakeshore communities, where onshore flow will keep readings a bit
MONDAY THROUGH THURSDAY...Forecast confidence is medium.
An upper trough will progress from the Great Plains into the western
Great Lakes. An elongated surface low attendant to the upper wave
will lift northeast from the western Dakotas into southern MB/SK.
The associated cold front will cross southern Wisconsin Monday night
into Tuesday morning, with a brief increase in deep layer moisture.
The best chance for rain will be with the frontal passage, however
upper support will be pulling away during this time. Rainfall
amounts should average 0.10 to 0.3 inches. Surface high pressure
will build into the upper Midwest following this system. Very mild
temperatures will continue as mild Pacific air is advected into the
area via quasi-zonal flow.
AVIATION/12Z TAFS/...VFR conditions today and tonight. A wswly
low level jet of 45-50 kts may create LLWS for tonight.
MARINE...Sely winds today veering sw then west throughout
tonight. Wly winds to continue on Sat. The winds and waves will
remain below Small Craft Advisory criteria.
Record highs for Milwaukee and Madison are as follows...
LOCATION FRI/17TH SAT/18TH SUN/19TH MON/20TH
Milwaukee 55 (1981) 57 (1933) 59 (1981) 60 (1930)
Madison 61 (1981) 57 (1981) 60 (1981) 57 (1930)
The average highs during this period are 33 (17th-18th) and 34 (19th-
20th) at Milwaukee, and 32 (17th-19th) and 33 (20th) at Madison.
TODAY/TONIGHT AND AVIATION/MARINE...Gehring
Saturday THROUGH Thursday...SPM