Area Forecast Discussion
Issued by NWS Bismarck, ND

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
FXUS63 KBIS 291350

Area Forecast Discussion
National Weather Service Bismarck ND
850 AM CDT Thu Jun 29 2017

Issued at 847 AM CDT Thu Jun 29 2017

Widespread showers and isolated thunderstorms developing across
southwest and south central North Dakota this morning. Another
line of showers with a thunderstorm embedded was moving through
northwest North Dakota along and ahead of a cold front. Current
forecast looks good but beefed up the chance for precipitation
across the northwest this morning.

UPDATE Issued at 641 AM CDT Thu Jun 29 2017

Showers continue to gradually develop over southern locations.
Expect this to continue through the morning as a compact wave/low
slides into the area. Going forecast has this reflected well.


.SHORT TERM...(Today and tonight)
Issued at 255 AM CDT Thu Jun 29 2017

Latest water vapor imagery shows a closed upper low circulating
near/along the central Manitoba/Ontario border with a couple of
shortwaves rotating through. Of particular interest for southern
ND is a shortwave sliding through northern Wyoming early this
morning, which develops a mid level closed low/700mb by 12z
Thursday near Sioux County. Ongoing/increasing synoptic scale
ascent ahead of this shortwave in southeast MT and northwest SD
early this morning per Bowman radar, will shift across southern ND
through the morning and into the afternoon. Low level frontogenesis
also intensifies and aligns with the large scale ascent. Nearly
all model solutions advertising a swath of light rain showers
southwest through south central, and into the James River Valley
through mid afternoon. Have refined pops to likely and categorical
within this area.

Another shortwave trough in south central Saskatchewan is supporting
a surface cold front now located from southeast Saskatchewan into
northern Montana. This cold front will push into northwestern ND
12z-15z Thursday, then slowly shift from northwest to southeast
later this afternoon through the overnight period. Instability
parameters are weaker with the GFS (ML CAPE less than 1000 J/kg in
the northwest), while the NAM indicates a moderate amount of
instability with ML CAPE nearing 2000 J/Kg. Both show mid level
lapse rates around 7C/Km/conditionally unstable. Both models
indicate weak 0-6km bulk shear of around 20kt. Thus, with
proximity of the cold front and enough instability present,
expecting scattered showers and thunderstorms west and north, but
deep layer shear is absent and thus not expecting any organized
severe thunderstorms to materialize at this time. Highest
thunderstorm chances today will continue across the west and
north, closest to the surface cold front and its movement to the
southeast later this afternoon.

.LONG TERM...(Friday through Wednesday)
Issued at 255 AM CDT Thu Jun 29 2017

Despite cool temperatures Friday, clouds and the threat for
showers will both decrease from west to east through the day.
Highs will be in the upper 60s to lower 70s.

Saturday through Wednesday, 500mb height fields continue to rise
through the period, indicative of a warming and drying trend. Thus
expect highs in the 70s to lower 80s over the weekend, then upper
80s to lower 90s Monday through Wednesday. Chances for precipitation
for look meager at best, so expect plenty of dry time in the long
term period.


.AVIATION...(For the 12Z TAFS through 12Z Friday morning)
Issued at 641 AM CDT Thu Jun 29 2017

Scattered to numerous showers develop southwest into central this
morning, which may lead to brief visibility restrictions to MVFR
levels. This afternoon, isolated to scattered thunderstorms will
develop which may linger into the evening. Early Friday morning,
localized MVFR cigs may develop over northern and eastern
locations. Otherwise, VFR conditions will prevail.




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