Area Forecast Discussion
Issued by NWS Grand Forks, ND

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473
FXUS63 KFGF 310008
AFDFGF

Area Forecast Discussion
National Weather Service Grand Forks ND
708 PM CDT MON MAY 30 2016

.UPDATE...
Issued at 650 PM CDT Mon May 30 2016

Adjusted POPs for current radar trends, as there has been two
bands of convection one near the warm front and another further
south with some mid level warm air advection. The HRRR continues
to do a fairly decent job with the current convection, and will
continue to follow the general pattern of the current bands of
thunderstorms slowly lifting northeast before they are consumed by
the main precip shield coming out with the surface low later
tonight. Included a heavy rain mention for a while this evening as
with weak flow aloft the convection has been moving extremely
slow.


&&

.SHORT TERM...(This evening through Tuesday night)
Issued at 301 PM CDT Mon May 30 2016

Forecast challenge for the immediate short term will be timing of
convection as well as severe potential given portions of south
central and southeastern ND are in a severe thunderstorm watch.
The HRRR has performed well with band of convection initiating
along a warm front parallel to and south of Highway 2 around
Devils Lake. Will generally follow HRRR guidance through at least
03Z, at which point more widespread activity initiating to our
west will move into the FA.

SPC mesoanalysis currently showing a band of 1000+ J/kg MU CAPE
along and south of the Highway 2 corridor, with the most recent
update extending east of Grand Forks to near the western edge of Red
Lake county. This is also on the nose of theta e ridge extending
up from the south. HRRR has indicated this and expect an
increasing chance that new storms may develop further east along
this line.  However, any convection to the east of what is
currently on radar has very little shear, and the current storms
are barely pushing 30kts 0-6 KM bulk shear. Consequently, although
pulsey, current storms have little movement and have been short
lived. Higher shear to the west will give a better chance for
stronger or severe storms closer to peak heating in one to two
hours.

HRRR brings the more scattered to numerous activity into the Valley
City area by 00Z to 02Z timeframe and this area will have heated
out further by then as the majority of SE ND is currently clear.
Best chances for severe in our FA will likely be Valley City down
through Lisbon and west. SPC will be issuing a severe weather
watch for the majority of the CWA along and south of Highway 2.
The primary threats will be one inch or higher hail and winds of
58 knots or greater, and an isolated funnel is certainly possible
along the warm frontal boundary to the south of Highway 2.

Models indicating clearing occurring in the far west beyond 04Z,
so have began to draw in a dry slot although further redevelopment
will be back in n central and nw ND. Surface low lifts into
southern Manitoba by Tuesday morning and more showery activity
will occur across the far north but should be dry across the
southern third tier of counties. Sfc low then slowly wobbles
across southern Manitoba though the day Tuesday and Tuesday night.

.LONG TERM...(Wednesday through Monday)
Issued at 301 PM CDT Mon May 30 2016

Wednesday will be much cooler as a front moves across the region
anticyclonic flow associated with sfc low in SE MB/SW Ontario
will keep skies cloudy and a chance for scattered showers across
much of the northern half of the CWA. Atmosphere will begin to
dry out from west to  east in the afternoon hours, however late
clearing will hold daytime highs in the upper 50s for the far
northeast.

For Thursday night through Monday...Zonal flow starts out the
period, but as the ridge across the western states starts to build
the flow becomes northwest. Models show sfc low pressure dropping
thru the FA early on, bringing some chances for pcpn mainly Thu
night through Sat. Most of the Sunday and Monday time frame looks
quiet. Temps should be fairly close to normal, or a little bit above.

&&

.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 650 PM CDT Mon May 30 2016

All TAF sites will either be VCTS or TSRA tonight as several bands
of convection lift northeastward across the forecast area this
evening before they are consumed by the main area of thunderstorms
coming out into the Red River Valley later tonight with the main
surface low. For now kept conditions VFR with just some CB mention
but heavier rain over a TAF site could bring vis down for a brief
period. A better chance for some lower conditions will be later
tonight and early tomorrow morning under the main surface low.
Ceilings of 800-1500 ft will be possible at most TAF sites around
daybreak. Showers and thunderstorms will be winding down by that
point and all but KBJI should be drying out by mid morning.
Improvement to VFR conditions by late in the period. Winds will be
all over the place with thunderstorms, but should eventually
increase out of the south tomorrow as a warm front pushes north of
the TAF sites.

&&

.FGF Watches/Warnings/Advisories...
ND...None.
MN...None.
&&

$$

UPDATE...JR
SHORT TERM...Speicher
LONG TERM...Godon/Speicher
AVIATION...JR



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