490 
fxus63 kgrb 052029 
afdgrb 


Area forecast discussion 
National Weather Service Green Bay WI 
329 PM CDT Sat Jul 5 2008 


Short term...tonight through Sunday...one more quiet night as 
high slowly drifts east. Temperatures today running a bit cooler 
than earlier expected...especially north central as more cumulus than 
expected developed. Area of moisture near 850mb to lift north 
tonight...with cumulus also diminishing with loss of daytime heating. 
Some cirrus also drifting over area. Have tweaked temperatures down a bit 
tonight...mainly east central where winds to be lighter. 
Trajectory forecasts suggest middle 50s this area. 


Frontal boundary approaches northwest WI late Sun afternoon. Upper support 
minimal though moderate southerly flow to bring increasing 
moisture north...going on over northern plains at this time. 
Models still appear to be overdoing dew points for Sun afternoon 
over state. Did not make any changes to previous thinking staying 
dry east through the day...thinking precipitation to get going closer to 
the front during the afternoon. 


North central and central counties still in slight risk area for 
sun...though shear minimal and instability not impressive. Expect 
any severe will be isolated at most. 


Long term...Sunday night through Saturday. Unlike most of the Summer 
season so far...the upper air pattern is forecast to become more 
zonal over the next week or two. There will be a few shortwaves 
that move through the flow every few days and bring fronts along 
with showers and thunderstorms. The hard thing will be to forecast 
their southward movement and their northward return. A front now 
in the Dakotas is forecast to arrive in our area Sunday afternoon 
and stall out Monday...before getting shoved to the south Tuesday. 
Best combination of upper support and low level moisture seem to 
be Monday and Monday night. High precipitable water values and the 
Prospect of slow moving thunderstorms could produce locally heavy 
rains in the southern part fo the forecast area. Dry slightly 
cooler air arrives Tuesday night and remains through Thursday as 
upper flow becomes northwest for a brief time. Upper flow forecast 
to become zonal again next Friday. Gulf mositure will move north 
once again and bring the Prospect of thunderstorms next weekend. 
Severe threat increases next Saturday and Sunday is GFS BUFKIT 
forecast soundings are anywhere near correct. 4000 j/kg cape and 
significant wind field forecast in northern and central Wisconsin. 
Big question is whether the middle level cap will be broken. 
&& 


Aviation...profilers showing low level winds increasing at this time. 
Low level wind shear marginal for period late tonight western sites. VFR 
conditions expected through sun with current cumulus north central 
diminishing quickly late this afternoon/evening. Frontal boundary 
to work towards state sun...with increasing chances of showers and 
thunderstorms 
&& 


Grb watches/warnings/advisories... 
none. 
&& 


$$ 
Te/rdm