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Area forecast discussion 
National Weather Service Grand Forks ND
320 PM CDT Tue Oct 25 2016

Short term...(this evening through wednesday)
issued at 257 PM CDT Tue Oct 25 2016

Main challenges will be timing and amount of rain tonight and
tomorrow as warm advection showers continue over southeastern ND
and have lifted north as far as Fargo to Cooperstown as well as
into west central Minnesota. Continue to see some sparse lightning
strikes west of the James Valley with Storm Prediction Center mu cape bringing some
weak instability into southeast ND, fairly well aligned with modest h700
frontogenetic forcing depicted on the 12z GFS, have included a
mention of isolated thunder across Ransom/Sargent/Richland
counties in the late afternoon to early evening hours.

Later tonight, GFS weakens the h700 fog band as it shifts into W
central Minnesota, thus majority of overnight period will be light to
moderate rain showers with the heaviest showers along and south of
Interstate 94. The targeted area for the highest rain showers
continues to be southern Minnesota with up to an inch or slightly
higher amounts in the far south....with a quick gradient to less
than one quarter of an inch north of Hwy 200. Sref/GFS and
conshort models are in general agreement with band of precip
expanding across most of eastern ND in the 21z to 00z timeframe as
weak mid level warm advection increases northward into northwest
Minnesota (gfs showing the strongest warm air advection will be just south of the
far southern valley in NE South Dakota into SW mn). Band of showers then
expands into southern Manitoba ahead of inverted trough, with sfc
front and highest rainfall amounts across southern Minnesota.

Tomorrow, model guidance shows gradual advection of band of
showers moving east of region by 21z however some lingering
showers will continue in the far east through the early evening.
Daytime highs will increase into the mid 50s, about 6 to 8 deg
warmer than today, west of the valley while clouds and precip should
bring cooler temperatures to the valley and eastern zones.

Long term...(wednesday night through tuesday)
issued at 257 PM CDT Tue Oct 25 2016

Wednesday night and Thursday...lingering damp conditions early
Wednesday should push out of northwest Minnesota during the evening a secondary shortwave trof dashes across the area.
Depending on cloud cover... lows could drop from the low 30s in
eastern ND into the mid to upper 30s in Minnesota lakes country. Thursday
should see generally dry conditions with partly cloudy skies and
seasonably mild temperatures.

Fast moving weather systems will be the rule through the late week
period and weekend. A warm, dry and southerly flow pattern on Friday
should turn cloudy, cool and damp by Saturday... as model guidance
comes closer into agreement. For now, Sunday looks to be continue
somewhat cool with a drier shortwave 500 mb ridging
passes quickly over the area.

Sunday night through Tuesday...will likley continue the unsettled
trend as a broad 500 mb trof is expected to spread across the western
half of the U.S. And keep the northern plains region in an overall
unstable flow pattern loft. In general, temperatures should average
just a bit above long term normals while precipitation trends
somewhat above normal as well.


Aviation...(for the 18z tafs through 18z Wednesday afternoon)
issued at 101 PM CDT Tue Oct 25 2016

VFR conds this afternoon will become MVFR tonight as rain showers
spread west to east across the region. Some models are indicating
IFR conds in the dvl region late tonight, which will be dependent
on where rain falls. Delayed onset of IFR but did bring it in by
the early morning period and rising again after sunset. Will keep
MVFR at all other sites.


Fgf watches/warnings/advisories...


Short term...speicher
long term...gust

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