Area Forecast Discussion
Issued by NWS Grand Forks, ND
FXUS63 KFGF 301132
Area Forecast Discussion
National Weather Service Grand Forks ND
632 AM CDT SAT JUL 30 2016
Issued at 630 AM CDT Sat Jul 30 2016
Increase the coverage areas of this mornings showers lifting into
the northern valley and NW MN. Efficient producers with no
lightning as radar estimates 1 to 2 inches in highly localized
locations...no ground truth as of yet this morning. Did also
increase PoPs in SW ND with showers east of BIS headed toward the
.SHORT TERM...(Today and tonight)
Issued at 335 AM CDT Sat Jul 30 2016
Challenges for today will be PoP coverage and or placement. Weak
warm air advection combined with a weak 500mb wave present in
water vapor imagery this morning over the central ND will allow
isolated showers and possibly a few claps of thunder this morning.
Redevelopment or continuation of convective activity is expected
in the afternoon and evening with a less than 20 kts of 0 to 6km
bulk shear and under 1000J/kg of CAPE...meager updraft strength
and minimally organized convection...will lead to a low threat
for severe storms. Temperatures will be very similar to Friday
with maybe a degree or two higher for maximums.
General thunder or shower activity may persist overnight into
Sunday morning. A warm overnight with lows Sunday morning in the
.LONG TERM...(Sunday through Friday)
Issued at 345 AM CDT Sat Jul 30 2016
Sunday into Monday will see a better chance for convection as
PWats increase with continued southerly blyr flow...values
up around 1.5 inches. This moisture will fuel storms Sunday
afternoon in western North Dakota initiated by fropa extending
south from a seasonally strong short wave in Canada. Thunderstorms
will move east into the western FA Sunday night...uncertainty
exists in their eastward progression with best forcing in farther
north in Canada. Current thinking is that activity will weaken and
then redevelop Monday afternoon with peak heating as the fropa
stalls out across the FA from NE to SW. Monday convection appears
to have a bit more shear available at this time with 40 kts of 0-6km
bulk shear. As a result SPC has the area in a marginal risk for
Monday for the possibility of severe hail and damaging winds.
Tuesday to Friday...
Relatively low amplitude long wave pattern through the period. Long
wave trough remains over the Pacific Northwest through the period
with broad southwest flow across the Northern Plains through day 5.
Some long wave ridge building occurs after day 5 over the northern
The ECMWF was a faster solution at the beginning of the period but
becomes slower then the GFS after day 4. The ECMWF has been trending
slower while the GFS was also trending slower but at a smaller
rate over the last couple model runs. Will blend the two models.
Little change to high temperatures from yesterdays forecast package.
High temps are a degree or lower for Tue and Fri. No change to Wed
.AVIATION...(For the 12Z TAFS through 12Z Sunday morning)
Issued at 631 AM CDT Sat Jul 30 2016
VCSH at GFK and TVF for the next couple hours...Afternoon
convection expected to be very spotty so will hold off on
mentioning in any TAF or for any time period...convection may
linger into the overnight period. Light southeasterly winds to
prevail with mostly VFR conditions.