038 
FXUS63 KBIS 300003
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
703 PM CDT Sat Jun 29 2019

.UPDATE...
Issued at 702 PM CDT Sat Jun 29 2019

Update to end the heat advisory. The impressive 
easterly/northeasterly outflow from the morning thunderstorms pretty 
much dominated the afternoon clouds, wind, temperature, and even 
dewpoint fields that were forecast. We had thought that the higher 
temps would eventually be realized by mid afternoon...but the 
temperature/humidity combination to make the heat index never came 
to fruition. 

UPDATE Issued at 610 PM CDT Sat Jun 29 2019

Update for tornado watch # 463 for parts of southwest and all of
south central ND...mainly from Dunn/Adams counties eastward to
Foster/Dickey counties...including Dickinson, Hettinger, Mandan,
Bismarck, Fort Yates, Carrington, Jamestown, Oakes.

&&

.SHORT TERM...(This evening through Sunday)
Issued at 331 PM CDT Sat Jun 29 2019

Main forecast issues this afternoon and tonight will be 
thunderstorms and heat.

The easterly winds and resultant cooler air from outflow from 
earlier thunderstorms has kept variable cloud cover over central 
North Dakota. Will take Stutsman County out of the heat advisory 
because of this.

Because of the outflow from earlier storms, and latest mesoscale 
analysis from SPC indicates that even at 2 pm CDT there is still 
some CIN that is still squelching the potential surface-based cape 
of 2500-5000 J/kg. However, the potential is still there with MU 
CAPE above the mixed layer of 3000-5000 J/kg. Low level jet still 
remains in place, with the northern edge of the LLJ and surface warm 
front now in southern Manitoba. The surface cold front has been slow 
to enter western ND today, but extended from near Williston to just 
east of Beach and Bowman. 

Despite the cooler air moving in, the latest RAP sounding for 
Jamestown indicates a return of warmer air (90F) by around 00z, and 
increases low level southeasterly flow. The current mesoanalysis 
from Bismarck to Jamestown indicates an effective significant 
tornado parameter of 4-9. Bulk shear is perpendicular to the north-
south cold front, so expect discrete cells to develop. Needless to 
say, plenty of available CAPE energy just above the surface, with 
higher dewpoints aloft as well with the LLJ, and plenty of effective 
shear remain. Large hail and damaging winds will be the main threat, 
as well as isolated tornadoes. Upper level impulses moving 
northeastward in the southwest flow aloft, along with convergence 
along the surface cold front advancing eastward into central ND will 
be the kicker for thunderstorms. Even now at mid-afternoon, upper 
level impulses are kicking off thunderstorms in northeast 
Montana/northwest ND/southeast Saskatchewan behind the cold front. 

Expect things to quiet down from west to east late tonight. Cooler 
and noticeably drier on Sunday with dewpoints in the 50s returning 
to our area.

.LONG TERM...(Sunday night through Saturday)
Issued at 331 PM CDT Sat Jun 29 2019

We return to more of a quasi-zonal flow through the remainder of
the long term period. So not quite the heat and humidity, but the
threat of thunderstorms will remain daily/nightly in the forecast.

&&

.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 702 PM CDT Sat Jun 29 2019

Thunderstorms are expected to develop over parts of central and 
western North Dakota - with best chances at KDIK until around 
03z...at KBIS and KMOT until around 05z...and at KJMS until around 
07z. Severe storms are possible with large hail, damaging winds, 
lightning, and possible tornadoes through 06z, especially at KDIK, 
KBIS, and KJMS. 

The cold front at 00z extended from east of Stanley to just east of 
KDIK to east of KHEI. The cold front will push east this evening, 
reaching KJMS by 05z-07z. Southeast winds ahead of the front and 
northwest winds behind it. VFR conditions later tonight and 
all day Sunday.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...JV
SHORT TERM...JV
LONG TERM...JV
AVIATION...JV