Area Forecast Discussion
Issued by NWS Grand Forks, ND

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FXUS63 KFGF 222352

Area Forecast Discussion
National Weather Service Grand Forks ND
652 PM CDT FRI JUL 22 2016

Issued at 652 PM CDT Fri Jul 22 2016

Storms have started over southwestern ND, and the question is how
they will evolve during the overnight hours. None of the models
have a great handle on current convection, although the 22Z run of
the HRRR is a bit better. Think that at least some of the
convection will hold together enough to impact our far western
counties later this evening, although with MUCAPE decreasing after
03Z over all but our far southwest it is uncertain how severe
storms will be. Will keep POPs ramping up during the late evening
and overnight over the western CWA, and will make further
adjustments at the mid evening update.


.SHORT TERM...(This evening through Saturday)
Issued at 305 PM CDT Fri Jul 22 2016

Main concern will be severe potential later tonight and
severe/heavy rain potential Saturday.

Deep/Severe convective across the western dakotas/eastern Montana
still anticipated with approach of mid level wave. Best low level
convergence over se Montana into western SD. The main question
will be if severe storms can hold together into any part of the fa
later tonight. Moist axis oriented from western ND into central
SD. The low level jet convergence remains well to our west
through 06z then shifts northward into S Canada later tonight.
After 06z cape across our FA drops off significantly. So at this
point do expect clusters of storms working east however do not
have a great deal of confidence severe storms will get too far
into the fa. With warm column in place temperatures will be mild
with muggiest conditions over the SW.

Severe threat continues tomorrow. Cold front should approach the
western fa at prime heating supported by relatively robust mid
level wave. Initially morning clouds from earlier convection may
suppress initiation somewhat however with plenty of support and
instability expect storms go get firing mid afternoon or so.
Storms will then track eastward during the evening. Concerning the
heavy rain threat guidance indicating e-w oriented warm front
from surface low in NE SD into central Mn where precipitable H20 values
from 1.5 to 2.00 inches may pool. This may be a focus for heavier
rain however overall main boundary looks progressive so at this
time not enough confidence to hoist and flood watch headlines.
This area has also had the least amount of rain over the past
week with 6 hour flash flood guidance from 2.5 to 3.5 inches.
This threat will of course have to be monitored. Prime threats
other than heavy rain will be large hail and damaging winds. Also
will see a tornado threat along warm frontal boundary/surface low
where ever that sets up. Temperatures will greatly hinge on cloud
cover during the day.

.LONG TERM...(Saturday night through Friday)
Issued at 305 PM CDT Fri Jul 22 2016

Not certain how fast the pcpn will exit off to the east Saturday
night. However, it seems like most models still show some lingering
pcpn, especially over the MN portion of the FA. This should finally
clear out though, so that Sunday will mainly be dry. The proximity
to the 500mb low may still yield some afternoon showers or possibly
thunder around the Lake of the Woods region.

Monday looks like a very nice day under weak high pressure at the
sfc. Afternoon high temps should top out in the 80s, but dew points
do not look quite as bad as they have been recently. Models show the
potential for another system moving across mainly the southern FA
Monday night into early Tuesday.

For the rest of the long term period, or Wed through Fri, the FA
will stay in a flatter zonal to northwest flow regime. Models are all
over the place in regard to additional tstm development, so
confidence is low. Will maintain low pcpn chances nearly this entire
time frame, although there will be dry periods too. Temps look to
stay barely below late July normals.


.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 652 PM CDT Fri Jul 22 2016

All sites are VFR with main mid and high clouds. Timing of
convection will be the main challenge. Think that KDVL should see
some storms later tonight, but it is more uncertain further east.
Will keep mention out for now, but think better chances for
convection will be tomorrow afternoon as a cold front approaches.
Have VCTS at various TAF sties through the end of the period. Will
keep cigs and vis VFR as they will not be reduced except under the
heaviest cells and exact placement of those is still uncertain.
Winds will shift from the east to southeast by tomorrow morning,
and KDVL will see winds going around to the southwest to west by
the end of the day as the frontal boundary approaches that site


.FGF Watches/Warnings/Advisories...


SHORT TERM...Voelker
AVIATION...JR is the U.S. government's official web portal to all federal, state and local government web resources and services.