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Area forecast discussion 
National Weather Service Grand Forks ND
638 am CDT Friday may 22 2015

Update...
issued at 637 am CDT Friday may 22 2015

Updated avaition section. No changes to forecast.

&&

Short term...(today through saturday)
issued at 317 am CDT Friday may 22 2015

High pressure over the area today with plenty of sun and
temperatures a bit warmer as well with most areas 70-75 for the
afternoon high. High and middle clouds from the system entering the
Central Plains will start to spread north later tonight into
Saturday...but do run into the high which will be sit along the
Canadian border. With high in place...prefer the slower European model (ecmwf) in
advancement of precipitation northward early in the weekend. 00z GFS
slower as well. Net result was to go dry all areas tonight then
restrict probability of precipitation Saturday to only the south half. Even this may be
too aggressive. Overall feel moisture will have a hard time
spreading north. Result is warmer and sunnier conditions north
Saturday and a bit cloudier and cooler south.

Long term...(saturday night through thursday)
issued at 317 am CDT Friday may 22 2015

The main issue into Sunday will be how far north any precipitation will
get. Once again high in place near the Canadian border so moisture
will run into a brick wall. Thus kept far northern areas dry through
Sunday with low probability of precipitation along Highway 2 and higher probability of precipitation south. The
placement of probability of precipitation will likely need to be tweeked in future forecasts.

For Monday through Thursday...main question for the extended
forecast period is the rate of eastward progress of protective
ridge over the northern plains. Both European model (ecmwf) and GFS agree that by
Memorial Day this will be evident as High Plains trough moves
toward the forecast area. So the signal for more active weather is
evident...but lack of any surface reflection the first couple of
days precludes confident placement and intensity of precipitation
at this time. Kept existing rain showers grids intact during most periods
with occasional mention of isolated thunderstorms and rain. Longer wave trough indicated
by European model (ecmwf) by Thursday completely out of phase with GFS...but if
correct would offer greater precipitation/thunder chances at end of time
frame. Highs in 60s Memorial Day owing to clouds/precipitation should
transition to 70s Tuesday-Thursday as showers become more sporadic.



&&

Aviation...(for the 12z tafs through 12z Saturday morning)
issued at 637 am CDT Friday may 22 2015

VFR through the period. Clear sky and a south wind near 10 miles per hour.

&&

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

$$

Update...Riddle
short term...Riddle
long term...wjb/Riddle
aviation...Riddle

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