134 
fxus63 kmkx 210829 
afdmkx 


Area forecast discussion 
National Weather Service Milwaukee/Sullivan WI 
329 am CDT sun Mar 21 2010 


Short term... 


Today...forecast confidence...high 


Current radar still showing returns over far southern WI. Not concerned 
with the possibility of snow though...as a northeast flow 
continues undercut the precipitation with drier air...with no 
observations reporting snow since earlier today. Forcing within 
baroclinic zone centered through northern Illinois will loosen today...as 
a milder airmass moves in from the west. Additionally...relative humidity forecasts 
show drier air continuing to push south through the state...with 
the clearing skies north to south across the County Warning Area during the day 
today. With the return of sunshine and 925 mb temperatures warming to 
2c-3c...should see a nice day with highs mostly in the upper 40s to 
lower 50s west. The exception will be near Lake Michigan where 
northeast winds should keep things a few degrees cooler. 


Monday and Tuesday...forecast confidence...medium to high 


Main story for the first part of the work week will be continued 
warming temperatures. Models 925 mb temperatures rise to 4c or 5c on 
Monday...with middle 50s expected most places. Cooler temperatures are 
likely near the lake again under northeast winds. The NAM is 
trying to show more of a northerly wind component in the east 
Monday afternoon...which could result in slightly warmer 
temperatures. Overall...undercut mav highs near the lake...but 
stayed a degree or two above the NAM. 


Southwest flow ahead of an approaching weak trough will bring in 
an even warmer airmass...with highs in the middle to upper 50s. 
Milder temperatures should generally push through to the Lake Shore with 
the offshore component. Models in decent agreement bringing the 
surface trough through Tuesday afternoon...with very limited moisture 
and lift across southern WI. Kept Tuesday dry as a result. 


Long term... 


Wednesday and Thursday...forecast confidence...medium 


Look for cooler temperatures on Wednesday behind the trough. With 
faster and weaker trough solution now favored in the 
models...dropped slight chance probability of precipitation for Tuesday night and 
Wednesday. Northerly flow will keep cooler and dry conditions 
across the forecast area on Thursday. Though highs will be cooler 
then earlier in the week...readings will still reach the lower 
50s...a few degrees above normal for late March. 


&& 


Aviation...middle level clouds over far south should thin later this 
morning as isentropic upglide and lower condensation pressure deficits 
further weaken over northern Illinois as low level winds become more northeasterly. 
Until then...ceilings will flirt with low VFR at kenw for a time this 
morning...with a few flurries possible. Cirrus should gradient thin through 
the day...with VFR conditions on Monday. Boundary layer mixing and 
dry surface air should prevent all but very patchy fog in low areas late 
tonight. 


&& 


Marine...have let Small Craft Advisory across southern zones expire at 08z. 
Winds have been slowly subsiding in the south since late Sat evening so 
expect wave heights to settle down as well. However...this area will remain 
on northern periphery of pressure gradient associated with strengthening low 
pressure over central MS valley so would expect wind speeds in excess of 
10kts through the day. Farther north...weak high pressure ridging will result 
in lighter onshore winds today but as low pressure to the south pushes 
east tonight and Monday...expect some tightening of pressure gradient and slight 
increase in onshore winds until Monday night. 


&& 


Mkx watches/warnings/advisories... 
WI...none. 
Lm...none. 


&& 


$$ 


Short/long term...ddv/07 
aviation/marine...mbk/11