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Area forecast discussion 
National Weather Service Grand Forks ND
624 PM CDT Friday Oct 24 2014

Update...
issued at 622 PM CDT Friday Oct 24 2014

No update necessary.

&&

Short term...(this evening through Saturday night)
issued at 230 PM CDT Friday Oct 24 2014

Forecast challenge for afternoon continues to be winds. Current observation
showing a few sites at 24 knots sustained wind speeds...still
slightly below advisory criteria. Will monitor 20z observation and if we
get more in the 25 to 26 knots range will likely issue
advisory...otherwise hold off. Have hires nmm in for wind grid
guidance and they seem reasonable. Next issue for short term will
be temperatures and have used a forecast blend for guidance.

Late afternoon...winds will approach advisory criteria (26 kts
sustained) around time of forecast issuance. Will monitor and issue if
needed. Vorticity over Manitoba lakes will continue into Ontario and
upper flow pattern will gradually turn more northwestward as ridge
amplifies over Pacific northwest.

Tonight...winds will subside across region by 06z to 09z timeframe
but continue around 5 to 10 miles per hour. Have lowered overnight temperatures 2 to
3 degree as model guidance seems a bit high with winds lightening after
midnight and clear skies.

Saturday and Saturday night...northwest flow pattern aloft Saturday with
upper ridge entering Dakotas Saturday night. Cooler air will
advect in and should see a dry and cool first half of the weekend.
Surface ridge will pass through County Warning Area Sat night and coolest temperatures will
be across northwest Minnesota...right around the freezing mark or even
cooler if winds go completely calm. Upper ridge overhead by 12z
Sun morning.

Long term...(sunday through friday)
issued at 230 PM CDT Friday Oct 24 2014

Sun and Monday...will transition to SW flow pattern aloft with a wave
entering Dakotas Sun afternoon. Warm advection will bring daytime highs
back into 60s on sun...with some showers developing east of the
river in the afternoon. 12z NAM did have negative showalters with GFS values
around zero...so included a mention of thunder for the late afternoon.
Models depiction of surface pattern still quite variable but appears
we could be in dry slot Monday with some wrap around in the northwest Monday
afternoon. Will remove probability of precipitation for much of the area and keep probability of precipitation along
the north and northwest.

Monday night through Friday...an upper trough moving across the
northern plains and into the Great Lakes will bring a continued
chance for precipitation Monday night into Tuesday as moisture wraps around
the backside of the low pressure system. Continued to keep probability of precipitation
going mainly in our north and east...and with 850mb temperatures dipping to
around -2 c...some snow showers could mix in during the coolest part
of the day. Temperatures will be much cooler than this week as highs dip
into the 40s and lows will be in the 20s. Another weak shortwave
will approach Wednesday and yet another on Thursday...keeping small
chances of precipitation through middle week. The shortwaves will also help
reinforce cool air and temperatures will remain slightly below average.
Friday should be cool and dry as models are in good agreement on
high pressure over the region.

&&

Aviation...(for the 00z tafs through 00z Saturday evening)
issued at 622 PM CDT Friday Oct 24 2014

VFR...cavu/cavok.

&&

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

$$

Update...voelker
short term...speicher
long term...Jr/speicher
aviation...voelker

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