Weather

336 
fxus63 kfgf 101928 
afdfgf 


Area forecast discussion 
National Weather Service Grand Forks ND 
228 PM CDT Friday Oct 10 2008 


Short term... 
intense band of rain from southeast ND through northern Minnesota associated with strong 
isentropic lift at 300-295k and strong 850 mb warm/moist advection 
will gradually shift east out of southeast ND late this after/early evening and 
out of west-central Minnesota (dtl-bji-pkd) by 06z. For the 
overnight...isentropic lift in the 750-850 mb layer greatly 
decreases and thus threat for precipitation is quite a bit less over the 
forecast area into early Saturday. 


The next surge in 850 mb warm advection/isentropic lift will arrive late 
morning and afternoon on Saturday with the focus just a bit farther 
north than on Friday...with the models indicate the main axis of 
precipitation 0.50 to 1 inch Sat afternoon/evening near a jms-Mayville-tvf-bde line 
north of a northward moving 850 mb warm front which by Saturday 
evening will be very near out southeastern forecast area. 


Saturday night into Sunday will see strong 500 mb low move into 
eastern Montana with surface low moving north northeast from Kansas/Nebraska into 
scntrl ND by 18z sun. Preference here is for the farther west surface 
low with track near a bis-dvl line on Sunday versus NAM which is 
more abr-gfk line. NAM remains a bit slower (about 6 hrs) than 
GFS. At this time GFS remains a bit preferred...but note that the 12z GFS 
is a bit slower than its previous runs. Net result is maximum isentropic 
lift north of 850 mb warm from from central into NE ND/far northwest Minnesota 
late Saturday night into Sunday midday with 1-2 inch rains very possible. 


For southeast ND/west-central Minnesota area gets into more a warm sector (at least at 
850 mb) and thus coverage of rain less. With focus of next heavy 
rain event Sat night-sun north of fridays heavy rain will not issue 
any flood watches. Rainfall rates so far even in todays rain slow 
enough to cause minimal troubles in terms of flash 
flooding....more of a standing water in ditches/fields 
scenerio/wet basements scenerio. 


Entire system shifts north Sun night into Monday with colder air 
coming in. Some wraparound showers possible. Kept mostly liquid except 
in dvl basin closer to 850 cold pool. 


Long term... /Tue through Friday/ 
after an upper low pulls out near the end of the short term...much 
colder air will move in Monday. Models are in some disagreement 
beyond Sunday....with consensus European model (ecmwf) showing a dry and seasonably 
cool period for Tue-Thu...with mainly zonal flow aloft. GFS does 
show some precipitation across the south...but again will go with consensus 
European model (ecmwf) in the long term. 




&& 


Aviation far and bji should see rain for remainder of 
afternoon...with ceilings taking dips into the MVFR range throughout 
the day. Rain will spread northward to gfk...tvf...and dvl by 
evening. Could see a break in rainfall early tomorrow morning 
before a second wave brings precipitation back into the taf areas by noon 
Saturday. Expect bji to drop to near IFR conds by early am 


&& 


Hydro... 
river flooding may well get going in the southern basin next few 
days as water runoff into the streams. Soils in southern valley and dvl 
basin are saturated. Rainfall rates appear not enough to cause 
real flash flooding...but soils such to keep water from seeping in 
fast. 


Fgf watches/warnings/advisories... 
ND...none. 
Minnesota...none. 
&& 


$$ 
Riddle/speicher