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Area forecast discussion 
National Weather Service Grand Forks ND
405 am CDT Friday Aug 22 2014

Short term...(today through saturday)
issued at 403 am CDT Friday Aug 22 2014

With the upper air pattern, the GFS and European model (ecmwf) were similar and
faster than the NAM and the Gem. NAM was the slowest model. At the
surface, the European model (ecmwf) was the slowest solution of the set. Will prefer
the European model (ecmwf).

Water vapor loop indicated a short wave trough over the Montana/ND
border. Short wave trough forecast to move into southern man this
afternoon. Will have scattered precipitation over the northern zones for
today.

Also water vapor loop indicated upper level low over the Pacific
northwest is forecast to amplify today, then weakens a bit. Trough
moves out of The Rockies and takes on a negative tilt and
intensifies again after 72 hours.

Also upper level low over the Desert Southwest will move into the
northern plains Sat/Sat night/sun and produce another round of
precipitation. 700 Theta-E ridge also moves over the area. Precipitable
water rises to to over 2 inches by Sat. Will add threat of heavy
rain for Sat afternoon and Sat night.

Long term...(saturday night through thursday)
issued at 403 am CDT Friday Aug 22 2014

/Mon through Friday/
the long range models are somewhat in agreement for next week with a
changing upper level pattern...however the GFS is faster with a
sharp short wave crossing the northern plains middle week. It is also
much drier with the European model (ecmwf) keeping precipitation across the southeastern
County Warning Area. Dry probability of precipitation for the majority of the County Warning Area (most of ND and northwest mn) on
Monday/Tuesday seem reasonable with upper pattern keeping best energy from
Central Plains into the Great Lakes. By Wednesday/Thursday the GFS builds a
ridge over Saskatchewan while the European model (ecmwf) is a bit further west with
the ridge axis and also less amplified. Day six showing some light
precipitation over area with the northwest flow pattern becoming dry at
night...which seems reasonable for northwest upper flow pattern. For late
in the week the GFS continues to amplify the upper ridge over the
northern tier and mb...keeping things dry...while the European model (ecmwf) has more
zonal flow with waves moving across southern Canada. Will lower inherited
chance probability of precipitation for the end of the week. Significant difference in model
solution begin on Friday...with the GFS showing a strong low bringing
precipitation to the area and the European model (ecmwf) continues the zonal flow
pattern...giving ME very low confidence in solution for day 7.

&&

Aviation...(for the 06z tafs through 06z Friday night)
issued at 1135 PM CDT Thursday Aug 21 2014

The hrrr indicates a fairly strong signal for IFR/LIFR conditions
developing overnight. Therefore...given the high surface moisture will
take ceilings down into the IFR category for all sites overnight. Low
ceilings and fog could linger well into Friday morning/early afternoon
with plenty of low level moisture...but will attempt to improve
conditions into MVFR category by afternoon.



&&

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

$$

Short term...hoppes
long term...speicher
aviation...dk

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