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Area forecast discussion 
National Weather Service Grand Forks ND
1120 PM CDT sun Apr 20 2014

issued at 1120 PM CDT sun Apr 20 2014

Southern end of rain band is beginning to Peter out and most
rainfall now confined to counties along international border. Expect this
to dry up before getting too far into Roseau County ... so will
readjust probability of precipitation and go dry after 07z. Wind shift line now moving into
Fosston area...with southern end just clearing Fargo. Will fine
tune overnight winds and no other changes planned.

Update issued at 919 PM CDT sun Apr 20 2014

Latest radar showing a band of light rain showers along a Walhalla
to New Rockford line...with some ground truth confirming rain is
making the surface in both Langdon and Devils Lake. Web cams
showing enough to wet the streets in Devils increased
probability of precipitation to scattered rain showers. Rap13 doing a decent job handling the
precipitation...which the model shows petering out around 09z. So in
addition to some increased probability of precipitation through 06z...will also remove
probability of precipitation after 09z and keep the isolated mention in from 06z to 09z.
As far as temperatures go...did lower the temperatures in the western and
southern zones where winds are light now (south) and will become
light by morning (west) as dewpoints are rather low and falling
into the upper 30s is possible. No other changes expected with the
10 PM update.

Update issued at 634 PM CDT sun Apr 20 2014

Visible Sat showing broken to overcast skies across most of eastern
ND. WV showing upper wave moving out of southeast Saskatchewan into mb...with
rain spreading across southern mb and portions of north central ND. Very
dry low layers this afternoon...especially in the south where relative humidity values
have dropped below 20 per central. May be difficult to get measurable
precipitation to the surface...but will keep idea of isolated showers across the
far north...although sprinkles if anything the more likely
scenario. Will increase sky across the western zones and northern
valley...other than that forecast in good shape.


Short term...(this evening through Monday night)
issued at 255 PM CDT sun Apr 20 2014

Forecast challenges will be precipitation chances along the cold front
coming through tonight and with the next system Tuesday night/Wed.
Models seem to have scaled back on extent of precipitation tonight. As of
middle afternoon temperatures have been a little slow to rise in the
northern valley and into portions of northwest Minnesota. The northwest
is also getting a little more cirrus now ahead of the surface low over
northwest ND. Cold front extends south from the low back toward
kdik with decent west-northwest winds behind it. There have been echoes
along the front over northwest ND but have yet to see something
actually reach the ground. As the front marches to the east
tonight there could be a few showers or sprinkles along it...but
overall not too excited about much more than that. The surface low is
expected to reach kdvl about 00z...the northern valley about 03z
and the Lake of The Woods closer to 06z. Winds across the higher
elevations from kdvl to khco may see some gusty winds behind the
front by middle to late evening. Temperatures will drop behind the front so
highs Monday will be cooler than today. Also expect the winds to
increase again on Monday morning.

Long term...(tuesday through sunday)
issued at 255 PM CDT sun Apr 20 2014

Looking at surface high pressure moving in for most of Tuesday with some
light return flow getting going by afternoon. Next system will
begin to arrive Tuesday night and even then mainly after midnight. Not
seeing much instability so kept the precipitation type as just showers. Did
keep some isolated afternoon thunder in the southwest on Wednesday but
confidence in that pretty low at this point.

For Wednesday night through Sunday...a very active pattern is expected Wednesday
night through Friday. Strong moisture transport will begin Wednesday and
continue Wednesday night...therefore expect rain showers to be fairly
widespread across the region. Can/T rule out a rumble of thunder Wednesday
night...but will not mention with instability very weak as we remain
in the cool sector. Precipitable waters will remain near 1 inch through Thursday
morning. Thereafter...a strong low will develop somewhere near the
Minnesota arrowhead...with deformation type precipitation. There are
indications that rain could change to snow late Thursday afternoon and
snow is possible Thursday night into Friday. The European model (ecmwf)/GFS and Gem all agree
that there could be some accumulation as well...given the potential
for fairly heavy precipitation in the north and east. Given the time of
year...we will have to see how precipitation rates develop...but Don/T put
the shovels away just yet. Temperatures will be well below normal by
Friday...and moderate some by next weekend with more of a split flow
and dry weather.


Aviation...(for the 06z tafs through 06z Monday night)
issued at 1120 PM CDT sun Apr 20 2014

Wind shift will reach bji within next two hours. Will not
introduce precipitation into tvf or bji as the showers are beginning to
dry up as they enter Minnesota. Light westerlies with winds shifting to
the northwest tomorrow morning...and becoming rather breezy by middle
morning. Did keep some stratocu in but raised ceilings to around 5k feet
(from 3k ft). Not overly confident this will be a ceiling
bottom line is VFR conds and windy on Monday.


Fgf watches/warnings/advisories...


short term...godon
long term...godon/dk