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Area forecast discussion 
National Weather Service Grand Forks ND
947 am CDT sun Sep 21 2014

Update...
issued at 947 am CDT sun Sep 21 2014

Clouds will continue to be the main challenge for today.
The convective temperature will remain low this afternoon due to
higher 925mb-850mb moisture. Increased cloud cover and extended
into the early evening hours east of the valley. This also led to
decreasing maximum temperatures a bit. Locations west of the valley should
also develop cumulus by late morning...but coverage should be more
scattered and then eventually erode from west to east (as ridging
builds from the west).

&&

Short term...(today through monday)
issued at 359 am CDT sun Sep 21 2014

Upper level trough over California forecast to move into the northern plains
by Tuesday. Precipitable water rises over an inch by Tuesday and approaches
an inch an a quarter to an inch and a half by 84 hours. Despite
impressive precipitable water, instability remains on the west side
of the trough axis. So mostly warm advection precipitation is expected for
Tuesday through Wednesday night. Will go for showers with isolated thunder.

For this morning water vapor loop indicated a short wave over WI and
another secondary lobe over northern Minnesota. Light showers were
occurring over the far northeastern zones. Will add low probability of precipitation for
this morning over the far east zones. Model soundings indicate temperatures
increase above 850 hpa and create a cap aloft by 7 PM CDT today.
Temperature continue to increase aloft through Monday afternoon. An inversion
lowers to just off the surface by Monday afternoon. Will go cooler for
today.

Long term...(monday night through saturday)
issued at 359 am CDT sun Sep 21 2014

For Wednesday through Sunday...models in good agreement. Some
differences Wednesday as a 500 mb short wave trough lifts northeast
from Wyoming and Colorado into eastern North Dakota Tuesday night
into early Wednesday. Precipitation with this system is mostly on the
south and east side of the this wave and pretty limited. 00z European model (ecmwf)
remains a bit wetter than the 00z GFS. Maintained chance
probability of precipitation...highest in Minnesota forecast area. Thereafter a deep 500 mb
trough moves into the West Coast and a 500 mb ridge builds into the
northern plains Thursday-Sat with warm and dry weather. 00z GFS breaks down
the ridge a bit faster in the late period than the European model (ecmwf) and in many
cases the slower so line is best. All blend probability of precipitation followed the drier
solution. Temperatures will rise to well above normal levels late
week.

&&

Aviation...(for the 12z tafs through 12z Monday morning)
issued at 700 am CDT sun Sep 21 2014

Fog loop indicated western edge of IFR ceilings extended from near hco
to ffm and was moving to the south at 20 to 25 knots. However fog
loop also showed clouds were shifting a little to the west. Will add
tempo groups for IFR ceilings at gfk and far this morning. May have to
keep low ceilings until later this afternoon. Expect more scattered-broken ceilings
as one GOES farther west of the Red River. Clouds should break up
late this afternoon and early evening. Clouds will exit eastern
zones later this evening.

&&

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

$$

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

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