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000 
FXUS63 KMKX 252340
AFDMKX

Area Forecast Discussion
National Weather Service Milwaukee/Sullivan WI
540 PM CST Sat Feb 25 2017

.UPDATE...

UPDATED FOR 00Z TAFS.

&&

.AVIATION/00Z TAFS/...

VFR through the TAF period. High clouds will increase this
evening, with mid-level clouds spreading in from west to east 
tonight. Look for gusty southwest winds during the daylight hours 
on Sunday.

&&

.PREV DISCUSSION... /Issued 307 PM CST Sat Feb 25 2017/ 

SHORT TERM...

TONIGHT AND SUNDAY... Forecast confidence is high.

Look for clear skies early this evening. Then mid level clouds 
associated with warm air advection will slide into southern WI by 
midnight. Temps will fall quickly during the evening, and then rise 
a couple degrees by morning. 

The nose of the low level jet will slide through southeast WI Sunday 
morning, just ahead of a weak mid level shortwave trough. This could 
be enough forcing for a few flurries/sprinkles toward central WI, 
but northern WI will have the better chance of light snow. There 
is quite dry air near the surface which will keep any precip 
aloft from making it to the ground in southern WI. Max temps 
Sunday will be in the lower 40s on gusty southwest winds.

SUNDAY NIGHT AND MONDAY...Forecast Confidence...High

Breezy southwest winds will push milder air back into southern 
Wisconsin, with above normal temps likely.

Partly sunny skies are then expected Monday with high pressure 
over the Great lakes Region. However lower level RH increases and
some stratocumulus could spread into the southeast late. Milder 
temps will remain in the area, with highs running about 10 degrees
above normal for late February. 

LONG TERM...

MONDAY NIGHT THROUGH WEDNESDAY...Forecast Confidence...Medium

Models in decent agreement showing two weak mid level shortwaves
in the southwest flow Monday night and Tuesday, as one Jet max
pushes across the Great lakes, while a second one is associated
with the advancing mid/upper trough that reaches the mid and upper
Mississippi Valley. 

Weak low pressure passes across southern Wisconsin Tuesday into 
Tuesday night. Should see some precip arrive by later Monday night
ahead of the low. With a non-diurnal temperature trend with rising
temperatures, the precipitation should be mainly rain as it
arrives. Any mixed precip that does form is expected to 
transition to all rain by mid- morning on Tuesday as temperatures
continue to warm. 

Models are showing a secondary main surface low to move in behind
the first departing low. As temps cool behind the first system, 
this second low could bring a little snow Wednesday. There is less
confidence in this setup than with the first low due to model 
differences with placement, timing and strength of the second 
low. Models show this low strengthening, with the GFS a little 
quicker with the cyclogenesis

THURSDAY THROUGH SATURDAY...Forecast Confidence...Medium

Could see a little snow Thursday as a weak shortwave and
associated surface trough moves through. Low and mid levels are 
cold, so any precipitation would be light snow. 

Decent agreement among models for Friday, showing high pressure 
and cold temps. Temperatures will moderate again Saturday as the
high moves off to the east. 

AVIATION/00Z TAFS/...

Skies will gradually scatter out from west to east this afternoon. 
Mid level clouds will then spread into southern WI late this evening 
with a warm front. Look for gusty southwest winds during the 
daylight hours Sunday.

MARINE...

Brisk northwest winds will diminish this evening as strong low 
pressure over southeast canada moves out of the region. The small 
craft advisory will continue through 9 pm this evening. 

Winds will increase out of the southwest Sunday morning. Gale force 
gusts are expected for at least south of the North Point Light 
during the daylight hours on Sunday. Expect gusty winds north of 
there, but less confident on reaching gales. A small craft advisory 
will be issued once the current one expires.

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...None.
LM...Small Craft Advisory until 9 PM CST this evening for LMZ643>646.

     Gale Warning from 8 AM to 6 PM CST Sunday for LMZ645-646.

&&

$$

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