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Area forecast discussion 
National Weather Service Grand Forks ND
631 am CDT Tuesday Aug 4 2015

issued at 629 am CDT Tuesday Aug 4 2015

Forecast on track this morning...adjusted grids to match current
observations and trends.


Short term...(today through wednesday)
issued at 322 am CDT Tuesday Aug 4 2015

A persistence forecast for today as pattern/airmass very similar
to yesterday with northwest flow aloft and clear skies allow for full
solar. Temperatures again in the 75 to 80f in the Red River with a bit less in
the lotw area.

By Tuesday night 850mb flow becomes southerly and during the day
Wednesday precipitable waters increase substantially as values over 1.5 inches
are prognosticated by both the 00z GFS/NAM. This increasing moisture
allows for ml convective available potential energy in the 2000 to 3000j/kg Wednesday evening.
Combined with a weak 500mb short wave and a weak surface low
tracking across the central Dakotas creating 0-6km bulk shear
values in the 30 to 40 kts...Storm Prediction Center has included the area in the day
2 convective outlook for a marginal severe risk.

Long term...(wednesday night through monday)
issued at 322 am CDT Tuesday Aug 4 2015

A stronger wave and potential for another round of
thunderstorms...especially across the southern half of the forecast area...
on Thursday as instability will be stronger and the surface low a bit
more organized centered in South Dakota by 18z for the southern valley.
Bulk shear values appear to be less than on Wednesday leading to a
higher risk of heavy rain than severe potential.

Friday-Monday...models indicate fairly active flow through the
weekend before an upper ridge builds into the region early next
week. Cannot rule out thunder chances for most periods. 0-6km bulk
shear will be supportive for organized storms...just not sure
about instability (moisture return). Temperatures will be near


Aviation...(for the 12z tafs through 12z Wednesday morning)
issued at 629 am CDT Tuesday Aug 4 2015

VFR with light winds and sky clear today.


Fgf watches/warnings/advisories...


short term...jk
long term...jk/tg

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