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Area forecast discussion 
National Weather Service Grand Forks ND
1247 PM CDT Friday Sep 19 2014

issued at 1247 PM CDT Friday Sep 19 2014

The surface trough continues to move slowly across eastern ND...with
scattered showers and even a few thunderstorms continuing mainly
east of the Red River. The Devils Lake basin has seen some
clearing but the rest of the County Warning Area has remained cloudy. Lowered
temperatures a degree or two as many sites are still in the 60s. Most of
the current precipitation should transition into the eastern County Warning Area during
the next few hours...but if there is enough sunshine...we could
get some storms redeveloping later this afternoon as the next
shortwave digs down out of Saskatchewan. Will keep probability of precipitation going
mainly in the northern counties into this afternoon.

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 18z tafs through 18z Saturday afternoon)
issued at 1247 PM CDT Friday Sep 19 2014

First challenge will be determining how soon the low clouds will
exit kfar/ktvf/kbji. Think kfar/ktvf should occur by early to middle
afternoon while kbji may take just a little longer. After these go
think only some middle level scattered-broken clouds will remain. Last thing to
watch will be the wind switch. South-SW winds will slowly turn more
to the west-SW and then finally west to northwest behind the boundary. Wind
gusts have died down some at kdvl/kgfk with the most gustiness ahead
of the boundary or across our Minnesota forecast area right now. Next more organized
band of showers/thunderstorms should get going across the kdvl region by Sat
morning so will only mention at kdvl for now.


Fgf watches/warnings/advisories...


short term...hoppes
long term...Riddle

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