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fxus63 kbis 220852 
afdbis 


Area forecast discussion 
National Weather Service Bismarck ND 
352 am CDT Monday Mar 22 2010 


Short term...today through Wednesday night... 
currently...surface low pressure extended from southeastern Alberta 
across eastern Montana/Wyoming to the western Dakotas. A broad upper 
level trough with embedded shortwave energy was moving across 
Montana/Wyoming...with light rain showers/sprinkles depicted over 
eastern Montana and northeast Wyoming on regional radar displays. 


The broad upper level trough is expected to move across the state 
today and tonight. The surface low is expected to move/develop 
southeastward and should extend from northwestern Minnesota to 
eastern Nebraska by this evening. Expecting a good chance of rain 
showers today...mainly west and north...and rain or snow showers 
tonight. Winds will become northwesterly across the region and 
cooler air will move southward from Canada. Thus highs today should 
range from only 40 across the north to around 50 south. Lows tonight 
should be mainly in the 20s. 


On Tuesday northwest flow aloft will bring a few weak energy 
impulses to the region. Will keep a slight mention of rain or snow 
showers for the daytime period Tuesday. Cooler than Monday with 
highs only reaching the middle to upper 30s north to around 40 south. 


A bit warmer Wednesday as surface winds become southwesterly with 
the exiting high to the south and low pressure over central Canada. 
This warming will be ahead of a cold front that is forecast to drop 
southward out of central Canada...bringing cooler air again for 
Wednesday night and Thursday. Have not mentioned a chance of 
precipitation with this cold frontal passage...mainly because of 
northwest flow aloft without any embedded shortwave impulses to 
enhance lifting. 




Long term...Thursday through Sunday 
short wave ridging will approach western North Dakota 
Thursday...setting up a northeast to southwest temperature contrast 
(low 30s/middle 40s). A weak surface low will drag a warm front across 
the state on Friday with some modest warming...especially 
south...but only small precipitation chances. An upper trough will 
then drop through the state Friday night into Saturday and will 
maintain slight chance probability of precipitation. Expect slightly cooler temperatures 
Saturday in the middle 30s north to lower 40s south. By Sunday...the 
upper ridge begins to build in from the west...but there are still 
some differences amongst the various model/ensemble solutions 
regarding how quickly the milder air will push into western North 
Dakota. Regardless...the southwest counties are favored for a 
warm-up into the upper 40s/near 50. 


&& 


Aviation... 
surface low pressure will move east across North Dakota 
today...accompanied by showers...with the highest coverage expected 
over the northern half of the state affecting kisn/kmot. Only 
scattered/isolated showers...if any...are expected at kdik/kbis/kjms. MVFR 
ceilings and visibilities will spread from west to east across the state 
through the day. 


&& 


Hydrology... 
warmer temperatures on Sunday had not increased river flooding on 
gauged sites. Ice jams have caused some sharp increases in river 
levels...notably Pipestem creek near Pingree. However overland 
flooding continues in the south central as well as ice jam flooding 
in the little Missouri in the west. 


A Flood Warning for melting snow remains in effect through Tuesday 
afternoon for Dickey...LaMoure...Logan and McIntosh counties. 
Multiple roads remain under water with additional standing water in 
low lying areas. There is water moving over the spillway at the dam 
on Lake LaMoure. This is being monitored. Continued warm 
temperatures today will increase the potential for excessive 
runoff with additional Road closures possible. 


Point forecast for river flooding continuing for LaMoure on the 
James...Ludden dam on the James and near Pingree on the Pipestem 
creek. 


In the south central North Dakota Apple Creek near Menoken had 
fallen below flood stage but was forecast to rise to above 15 feet 
again this week. Flooding also continued on Beaver Creek at 
Linton...where the level remains in moderate flood category. The 
river is forecast to begin rising again today and crest 
again in the major flood category at 14 feet on Wednesday evening 
the 24th...then begin a slow fall. 


A Flood Watch continues for south and west of the Missouri River in 
anticipation of runoff from snow melt and ice jam problems as 
temperatures again reach into the middle 40s to lower 50s. This area 
west and south of the Missouri still has a moderate snowpack that 
should begin melting in earnest this week. 


&& 


Bis watches/warnings/advisories... 
Flood Watch through Tuesday morning for ndz017>020-031>034- 
040>045. 


&& 


$$ 
Short term/hydrology...jv 
long term/aviation...Kinney