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Area forecast discussion 
National Weather Service Grand Forks ND
940 am CDT Tuesday Sep 23 2014

issued at 940 am CDT Tuesday Sep 23 2014

Upper circulation continues to slowly approach the region. This
will spread clouds into the region...and southerly winds ahead of
this feature will be breezy. The 20-30 percent probability of precipitation for this
afternoon across far southeast North Dakota...and spreading
east/northeast tonight still appear reasonable. Will take a closer
look at incoming model guidance...but given the dry airmass in
place not sure much precipitation will actually reach the ground this far
north...although model soundings are fairly saturated.


Short term...(today through wednesday)
issued at 322 am CDT Tuesday Sep 23 2014

Short term issues involve precipitation coverage with upper low/surface low that
will move into the area later tonight. Early this morning the surface
and 500 mb low was near the Black Hills. Band of showers near the
Black Hills then weakening eastward into southeastern South
Dakota before showers increase in coverage southward into Kansas.
Models remain in good agreement in bringing high clouds with
system into southeast ND this morning followed by middle level cloud cover
this afternoon along with a few showers late in the day. With cloud
cover increasing and thickest in the southeast ND expect high temperatures today
to be several degrees cooler in that area (upper 60s-around 70)...while
the rest of the region sees mainly middle 70s.

Upper low will move into the Red River valley tonight. Sufficient
850-700 mb moisture present just south and east of the upper low
for some showers...but amounts light. NAM is a bit farther west
with light showers (back toward grand forks) vs the other models
which maintain them more so far southeast ND into north central Minnesota. GFS remains
drier than other models too. All in all 20-30 probability of precipitation for measurable
still seems reasonable. Likely sprinkles will reach a bit farther
west than pop area and this can be added as confidence increases.
Upper system will exit north central Minnesota Wednesday afternoon with clearing
move into eastern ND.

Long term...(wednesday night through monday)
issued at 322 am CDT Tuesday Sep 23 2014

Wednesday night will see the system pull east and clearing to progress
through northern Minnesota. 500 mb ridge builds as anticipated Thursday
into the northern plains with warming 850 mb temperatures into the middle to upper
teens at 850 mb. Thus idea of 80 to 85 for highs especially northwest forecast area
seem reasonable as this area closest to warmest air. 75-80 south
and east.

For Friday through Monday...models remain in good agreement with
respect to strong upper ridging across the region to start the
period. Expect mainly dry weather and above normal temperatures with
this feature.

Models diverge a bit by sun...but hint at a vigorous short wave crossing
the region. Most of the energy is expected to be in the northern part of
the area...and drag a cold front just over the Canadian
border...with chances for -shra/-tsra across the north. Behind the
wave...the upper ridge rebounds with continued warm temperatures and low
pop chances through the end of the period.


Aviation...(for the 12z tafs through 12z Wednesday morning)
issued at 623 am CDT Tuesday Sep 23 2014

Timing advance of high...then middle cloud...and then possibly MVFR
cloud cover as upper low moves northeast toward the Red River
valley over the next 12-24 hours. South-southeast wind will
increase middle to late morning...and be gusty at times in the Red
River valley to the middle 20kt range. Any light showers will hold
off at Fargo until after 00z. Some models show MVFR ceilings arriving
late tonight through 12z Wednesday in most areas of the Red River valley
into Minnesota. Unsure of that yet....but did keep previous idea of
ceilings around 3k feet moving in later tonight.


Fgf watches/warnings/advisories...

short term...Riddle
long term...Hopkins/Riddle

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