644
FXUS63 KBIS 040528
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
1228 AM CDT Thu Jul 4 2024

.KEY MESSAGES...

- Scattered showers and isolated thunderstorms will continue
  over much of western and central North Dakota through
  tonight.

- Numerous showers and scattered thunderstorms are expected on
  Independence Day, especially during the afternoon. But the
  entire day will not be a washout at most locations, as much of
  the activity will be of the "hit or miss" variety.

- Slightly below normal temperatures with daily chances for
  showers and thunderstorms will continue through the holiday
  weekend. Highs will mainly be in the mid to upper 70s.

&&

.UPDATE...
Issued at 1223 AM CDT Thu Jul 4 2024

Minimal changes were made to the forecast for this update.
Showers and thunderstorms continue to develop across the south
central, while some additional showers are expected to begin
moving into the northwest over the next few hours. Some light
radar returns are being observed near the west central border,
though its unclear whether the rain here is actually reaching
the ground. The lightning activity in the south central has died
down a bit, but isn`t completely gone. Otherwise, just blended
the current observations into the forecast.

.UPDATE...
Issued at 949 PM CDT Wed Jul 3 2024

The forecast for tonight remains on track. The greatest coverage
of showers is beginning to shift over south central North Dakota
as expected, ahead of the base of the mid level trough. This is
also the only part of the state where lightning is still being
observed. We will maintain an isolated thunderstorm mention for
most areas through the night with the continued presence of at
least a few hundred J/kg MUCAPE, but the probability of
lightning at any given location is quite low.

.UPDATE...
Issued at 719 PM CDT Wed Jul 3 2024

At 7 PM CDT, the greatest concentration of shower and thunderstorm
activity was located from Divide County to near Lake Metigoshe.
Elsewhere, showers and especially storms have been lower in
coverage than anticipated, although some more persistent rain is
now making its way into southwest parts of the state. PoPs have
been updated to better reflect observed trends this evening,
and CAM/rapid refresh model trends later tonight through
tomorrow.

&&

.DISCUSSION...
Issued at 330 PM CDT Wed Jul 3 2024

Currently in the cyclonic flow , several areas of popcorn
showers and thunderstorms have developed. A shortwave wave is
in central Montana, providing lift for these showers in eastern
Montana and the Dakotas. These areas are the northwest, north
central, and around Bismarck. Another area of showers is in the
southwest where a different system is bringing showers into the
state off a low moving into Nebraska. The showers in the diurnal
cumulus should die with the sunset, where as the showers off
the low may continue all night, slowly spreading north and east
as the upper level wave moves east.

Independence Day:

With the upper low and surface low moving across South Dakota
Thursday, another day of widespread popcorn showers are likely
in the afternoon. For the morning hours, it looks like showers
and maybe thunderstorms will be rotating around this low in
northern South Dakota and into the south central of North
Dakota. Timing on this looks to be through the late morning
before the daytime diurnal convection starts. As the wave passes
through, the flow aloft will turn northerly with an incoming
ridge. However this won`t prohibit the afternoon convection.
This looks to start around 17z as the diurnal cumulus starts,
moving straight south. Storms will not be severe as there will
be hardly any shear, plenty of CAPE though. Highs will be
slightly cooler in the low to mid 70s.

**If you look at your city`s forecast on our website, you`ll
 probably see a high percentage chance for storms. However the
 storms will be the popcorn version and not an all day washout
 like it may seem. So there will be quick moving small
 thunderstorms everywhere in the state in the afternoon, ending
 in the evening. With your outdoor plans, make sure to keep an
 eye on the sky for lightning and on the radar to see if one is
 coming or when you are in the clear. Remember, lightning can
 strike several miles away from the storm out of the anvil or
 sideways out of the storm.**

This weekend into next week:

Friday through Sunday will be more of the same with shortwaves
moving through with daily diurnally driven chances for showers
and thunderstorms. No severe weather is expect because everyday
one of the key ingredients will be missing, either CAPE or
shear. Highs through the weekend will remain just below average
in the low to upper 70s. After Sunday a big ridge sets up over
the western Continental United States, with warmer temperatures
at 850mb. So starting Monday, a warming temperature trend will
start with highs ranging from the mid 70s to the lower 80s. By
Wednesday it could range from the mid 70s to mid 80s. There
could be a few kinks of energy moving through the ridge
producing a few showers, but otherwise it should be mostly dry
under the influence of the ridge.

&&

.AVIATION /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 1223 AM CDT Thu Jul 4 2024

Showers and thunderstorms will remain possible overnight, with
the highest chances near KBIS. Through the day today, frequent
showers and thunderstorms can be expected across the entire area
and at every terminal. However, given the spotty nature of these
showers, it will be hard to tell exactly when any given location
will see rain. In any storm that develops, gusty winds and IFR
visibilities may be possible. Otherwise, mostly VFR to
occasionally MVFR ceilings are expected through the TAF period.
Winds will be 5 to 10 kts, generally out of the northwest.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

UPDATE...Besson
DISCUSSION...Smith
AVIATION...Besson