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Area forecast discussion 
National Weather Service Grand Forks ND
942 am CDT Friday Sep 19 2014

Update...
issued at 942 am CDT Friday Sep 19 2014

Web cams in the northwestern counties have shown at least some
rain starting to reach the ground and radar returns have been
intensifying near the surface trough axis. Bumped up probability of precipitation to scattered
in the northwestern counties a bit earlier than we originally had
in the grids. Precipitation continuing to move across the southern
counties will continue to push northeastward. Kept probability of precipitation mostly
scattered except along the far eastern border during the next few
hours and in the north along the front coming down later today.

Update issued at 644 am CDT Friday Sep 19 2014

Tweaked probability of precipitation for this morning...shifting probability of precipitation a little farther
south. Radar indicated some thunder northwest of Fargo and near
Warroad Minnesota. Otherwise showers were southeast of a line from hco to
New Rockford. Showers were moving northeast about 35 knots. No other
change made a this update.

&&

Short term...(today through saturday)
issued at 400 am CDT Friday Sep 19 2014

Different regimes forecast for the next couple days.

Precipitable water rises between an inch and an inch and a half for
today. Water vapor loop indicated an upper level trough over western
Montana. Trough will move across the forecast area today. Upper level jet
was on the east side of the trough. Rain over the northern plains
was occurring along the 700 hpa Theta-E ridge. Rain and Theta-E
ridge will shift east during the day. Problem today is a dry layer
is forecast between 850 and 700 hpa that precipitation aloft will have to
overcome. Low ceilings over Nebraska forecast to move north into the area
this morning and fog loop shows clouds moving North.

East west cross section suggest a front at the surface and a front
aloft follows Friday night and later Friday night respectively. Problem
with dry layer remains at low levels.

Models forecast a 120+ knot upper jet to punch into the area Friday
night/Sat as upper trough now over British Columbia will move into the northern
plains. Showalters become negative and 500 hpa temperatures fall below -20c
on Sat. Will go for thunder Friday night/Sat.

Long term...(saturday night through thursday)
issued at 400 am CDT Friday Sep 19 2014

For Monday through Friday...500 mb ridge will be in place over the
area. Models coming into a bit better agreement in have a 500 mb
low over Idaho move east and the northeast Wednesday-Thursday into the northern
plains. Moisture with this system not impressive but confidence
enough to continue mention of showers/T-storms with this system Wednesday
exiting Thursday. Majority of the models keep the best chances from
central Kansas into western Minnesota. Area offices toned down probability of precipitation
given from all blend tool on Friday as it wasnt supported by
models. Overall next week will feature temperatures above normal.

&&

Aviation...(for the 12z tafs through 12z Saturday morning)
issued at 644 am CDT Friday Sep 19 2014

Fog loop/surface observation indicated MVFR to IFR conditions were over
eastern South Dakota. Clouds were moving north at approximately 30 knots.
Clouds are expected to move north and east into southeast ND and
much of northwest Minnesota through 10 am. The MVFR/IFR deck should shift
east out of the area by middle afternoon. Cold front will move through
the area and winds shift to the northwest on the ND side this
afternoon and the Minnesota side this evening.



&&

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

$$

Update...Jr
short term...hoppes
long term...Riddle
aviation...hoppes

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