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Area forecast discussion 
National Weather Service Grand Forks ND
1023 am CDT Friday Aug 28 2015

Update...
issued at 1019 am CDT Friday Aug 28 2015

Initial band of storms dropping southeast from Manitoba was severe
with large hail Winkler mb to Pembina ND region. These are
weakening. Question will be re-development. Upstream wind field is
quite chaotic and hard to tell where any trough is located. That
said some low level boundaries present with the remaining showers
dropping south could help re-fire activity this afternoon. Hrrr and rap
indicate that to occur possibly jms-far-bji area 21z-00z period.
Did adjust probability of precipitation a bit to increase them this morning and adjust a
tad farther west and south today.

&&

Short term...(today through saturday)
issued at 355 am CDT Friday Aug 28 2015

Visibility across northwest Minnesota will continue to be variable
in patchy fog through the predawn hours... though any fog should
dissipate shortly after sunrise.

A strong thunderstorm complex in southern Manitoba this hour is
expected to diminish in intensity as it brushes the U.S. Border
across northern Cavalier and Kittson counties around 12z. Isolated
shower and thunderstorm activity is then possible through the
forenoon throughout the north border counties... spreading across
far northcentral Minnesota through the early afternoon.

A second round of scattered showers and thunderstorms are
possible...starting in east central ND from middle afternoon and
spreading eastward along an east-west oriented trough axis into
northwest Minnesota into the early evening. Extent and severity
of these storms will depend on afternoon heating... with afternoon
temperatures reaching into the middle 80s in spots... thus some
storms could produce small hail and gusty winds.

Later tonight and Saturday will see a return to light southerly
flow and a drier...more stable 500 mb ridge building in aloft.
Temperatures overall will be a bit warmer than seasonal normals.

Long term...(saturday night through thursday)
issued at 355 am CDT Friday Aug 28 2015

Saturday night and suunday...expect more of the same. With a warm
500 mb ridge aloft and light southerly winds at the surface...expect
seasonably warm and dry conditions with high temperatures ranging
form themid 80s in central Minnesota lakes country to the lower 90s
in the Devils Lake basin.

Monday-Thursday...a very Summer-like weather pattern will continue
heading into the start of September. The upper ridge will flatten
early on with shortwave energy passing north across Canada. An
associated weak surface boundary could fire a few storms off on
Monday...although the best upper support will be well north over
Canada. This boundary should then wash out within persistent
southwesterly flow aloft. Not very optimistic about precipitation chances
later in the period...although a storm could not be ruled out given
the southwest flow pattern/rather moist environment. Warmer middle-
level temperatures may act to suppress convection by Wednesday into Thursday as the
pattern amplifies ahead of an approaching front. Details out at this
range are still quite uncertain though.

Ave highs/lows fall into the middle to upper 70s/low 50s during early
sept...but highs should should reach the 80s with lows mainly in the
60s through Thursday. Wednesday and possibly Thursday look to be warmest as 850 mb
temperatures rise to near 25c. So some highs at or above 90 are possible.

&&

Aviation...(for the 06z tafs through 06z Friday night)
updated at 355 PM CDT Thursday Aug 27 2015

Patchy fog still possible in northwest and west cental minesota
through the early morning...largely dissipating with sunrise.
Isolated showers and thunderstorms expected along the north border counties
this forenoon... with scattered thunderstorms redeveloping in the middle afternoon
across east central ND and spreading into northwest Minnesota from late
afternonn into early evening.



&&

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

$$

Update...Riddle
short term...gust
long term...gust/makowski
aviation...Jr/gust

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