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Area forecast discussion 
National Weather Service Grand Forks ND
107 PM CDT Friday Aug 28 2015

Update...
issued at 102 PM CDT Friday Aug 28 2015

Biggest question is where/if T-storms will re-develop. Surface observation
show a south-southwest wind to 25 kts in the northern valley with temperatures
near 80 and dew points 65-70 in much of the Red River and east ND and far northwest Minnesota.
A weak wind shift is noted but more in central ND Rolla-Cando area
and into SW Manitoba. Convective short range models indicate a
weak wind shift dropping south this afternoon and some storms firing
Fargo-Detroit Lakes area 00z or so. That has been a consistent
signal but yet trough/wind shift line as depicted by hrrr still am
not sure will occur. Trended probability of precipitation the way of the hrrr and hop WRF
models which so the Fargo-dtl convection.



&&

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 18z tafs through 18z Saturday afternoon)
issued at 102 PM CDT Friday Aug 28 2015



Models are still hinting at thunderstorm development potentially
this afternoon. NAM and sref still point toward activity near
tvf/gfk by middle afternoon. However...the latest hrrr keeps activity
further east and south...more in the kbji to kfar areas around 00z.
Regarding ts...have made only minor changes compared to previous
forecast. NAM and sref are showing signs of br development late
tonight. Have kept it at 5sm around sunrise at gfk/bji/tvf.

&&

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

$$

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

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