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Area forecast discussion 
National Weather Service Grand Forks ND
1240 PM CDT Wednesday Oct 7 2015

issued at 1240 PM CDT Wednesday Oct 7 2015

Adjusted probability of precipitation a bit models continue to trend later with
precipitation development this afternoon. It does look like at least the
northern Red River valley will see likely rain through late
afternoon or early kept probability of precipitation high there. Lowered quantitative precipitation forecast
a bit also as there is still a lot of dry air to overcome and
think that lower amounts will reach the ground.

Update issued at 958 am CDT Wednesday Oct 7 2015

Main adjustment was to delay the onset of precipitation across the County Warning Area.
The hrrr...rap...and latest NAM all have precipitation starting near
21z. The hopwrf ensembles are also in pretty good agreement.
Additionally with the dry dew points currently it will take a
while to saturate when precipitation does develop. Have the likely probability of precipitation
holding off until near 21 to 00z. The precipitation still seems on track
for mostly the northern County Warning Area with the southern extent a bit more

Update issued at 745 am CDT Wednesday Oct 7 2015

We will let the frost/freeze headlines expire at 8 am...with
temperatures rising above freezing by 9 am. The rest of the
forecast is on track.


Short term...(today through thursday)
issued at 330 am CDT Wednesday Oct 7 2015

The main challenge will be shower/thunderstorm chances this
afternoon and overnight...and temperatures. Models are trending slower
and a bit drier/further north with this system overall. Prefer the
NAM that is in better line with the cam models with this northern
track of this fast moving clipper type system today and tonight.

For today...after a frosty early morning for most...clouds will
increase quickly from west to east by afternoon. We will delay the
shower and thunderstorm chances a bit...with most of the
convection arriving in the west around 18-21z...then into the
valley by 00z. There will still be strong forcing in the
north...with showalters slightly negative moving in from the west.
Precipitable waters should be near 1 inch...with all Pacific moisture moving in.
Winds will become breezy from the southeast with about 30kt to mix
this afternoon.

For tonight...the shower and thunderstorm chance will increase
into the valley and Minnesota counties from 00z-03z. There will be a lot
of dry air to overcome in all areas today and this
should hold overall quantitative precipitation forecast values down. This is reflected in the
latest HPC guidance that gives about one quarter of an inch in NE
ND...and perhaps up to one half inch into northwest Minnesota. The far southern
forecast area getting around one tenth of an inch or so...but this
could be variable depending on how many thunderstorms develop.
There will be a ribbon of 500 j/kg of 850mb cape along with
negative showalters...and steep middle level lapse rates quickly
moving west to east tonight. Winds will shift to the north behind
the front and could get a bit gusty west of the valley late.

On Thursday...the main lift and deeper moisture will shift east of
the region. There could be a band of lower clouds with the cold
advection and northerly winds...that could gust to 30 miles per hour or so in
the valley with favorable northerly winds behind the front and
30kt to mix. Temperatures should be in the middle 50s for all areas and
could be a few degrees colder in the north given the northerly
winds and low level cold air advection.

Long term...(thursday night through tuesday)
issued at 330 am CDT Wednesday Oct 7 2015

For Thursday night...expect a dry and seasonably cool night with lows
near 40 south and low/middle 30s north. Temperatures could be a bit cooler
with frost not out of the question with high pressure moving over
the region.

For Friday...strong warm air advection will begin with southerly winds increasing by
afternoon. Temperatures should warm above normal along and west of the
valley into the low/middle 60s with middle/upper 50s in the far east.

The Saturday through Tuesday period will be mainly quiet. An upper
ridge building across the area will bring drier westerly
winds...and temperatures rising to above normal values. By late
Sunday...a vigorous upper wave will cross the area dragging a cold
front with it. Behind the front...looking for breezy conditions with
cooler temperatures...and a chance for showers before high pressure
settles in again for the end of the period.


Aviation...(for the 18z tafs through 18z Thursday afternoon)
issued at 1240 PM CDT Wednesday Oct 7 2015

Challenging taf issuance with gusty south winds...20 to
25kts...expected this afternoon with increasing shower coverage.
Cold front to push through late evening into the overnight with
winds turning to the west and then northwest. Thunder possible but
coverage will be poor so left out of tafs for now. MVFR ceilings behind
the northwest wind shift/front expected at all sites excluding kfar. Gusty
northwest winds tomorrow morning...20 to 25kts.


Fgf watches/warnings/advisories...


long term...Hopkins/dk

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