668
FXUS65 KTFX 271814
AFDTFX

Area Forecast Discussion
National Weather Service Great Falls MT
1214 PM MDT Thu Jun 27 2024

...UPDATE AND NEW AVIATION SECTION...

.SYNOPSIS...

Strong thunderstorms are forecast for today. Some of these storms
may become severe, producing strong erratic gusty winds, large hail,
frequent lightning and heavy downpours. Temperatures cool through
the end of the traditional work week, with a few general
thunderstorms developing on Friday.

&&

.UPDATE...

Convection has significantly reduced available instability for
stronger end storms heading into the early afternoon hours;
however, There is still an opportunity for stronger storms to
develop over the central and eastern portions of the forecast area
heading into the early afternoon hours as CIN erodes and diurnal
heating helps recover at least some instability. Gusty winds,
hail, and brief downpours can be expected with the stronger
storms. Also LCL`s are very low, which may help spawn a few weak
funnel clouds. Precipitation diminishes from west to east later
this afternoon and westerly winds will begin to pick up by the
evening hours. Locations along the Northern Rocky Mountain Front
and adjacent higher plains may see gusts over 50 mph during the
passage of an elevated cold front. Pops, winds, and QPF were all
adjusted per current trends. - RCG

&&

.AVIATION...
27/18Z TAF Period

Showers and thunderstorms will move from west to east through the
late afternoon hours with low VFR/MVFR conditions in addition to
erratic, gusty winds, downpours, and lightning. The severe threat
has diminished some, but a few strong to severe storms can still be
expected, mostly for the KHVR and KLWT. Gusty westerly winds and
partial clearing take place tonight with locations along the
Northern Rocky Mountain Front and adjacent high plains (KCTB)
potentially seeing wind gusts over 40 kts along with mountain wave
activity after 28/00Z. Wrap around moisture then moves in from
northwest to southeast into Central/North-central Montana tonight
and Friday for MVFR clouds, showery conditions, and windy
conditions. - RCG

Refer to weather.gov/zlc for more detailed regional aviation
weather and hazard information.

&&

.PREV DISCUSSION...
/ISSUED 428 AM MDT Thu Jun 27 2024/

Note: The forecast area for The National Weather Service Great
Falls Weather Forecast Office includes north central, central and
southwest Montana.

Today...An upper level trof rolls across The Treasure State,
today, with the attendant cold front impacting our region.
Considering the timing of cold frontal passage, thunderstorms
develop early and continue through the day. Some of these storms
may become severe. The Storm Prediction Center (SPC) includes,
Meagher, Judith Basin and Fergus Counties in an area of Slight Risk
for Severe Weather. For this area, there is a 15% to 29% risk for
severe wind of >= 58 mph, 15% to 29% risk for large hail of >= 1"
and 2% to 4% risk for tornado. Some other portions of our region are
included in a Marginal Risk for Severe Weather. Across these areas,
there is 5% to 14% chance for severe wind and a 5% to 14% chance for
large hail. These probabilities are considered within a 25 mile
radius at any given point in the risk area. All of today`s
thunderstorms have the potential to produce frequent lightning and
heavy downpours. The severe weather threat is forecast to move out
of our area by late afternoon. Cooler temperatures, follow.

Tomorrow...Low elevation high temperatures range about 10 degrees
Fahrenheit below normal. Rainfall impacts north central and
central Montana, allowing for some needed moisture. Strong gusty
winds are forecast, especially along The Northern Rocky Mountain
Front. Considering cold and wet conditions, hypothermia becomes an
concern to those working or recreating outdoors.

Saturday through next Thursday...An upper level ridge dominates
the first part of the weekend favoring warming conditions and a
dry day. Low elevation highs return to near normal values. With
the approach of the next upper level trof, the weather becomes more
active, again, with daily showers and thunderstorms forecast
from Sunday through next Thursday.
- Fogleman

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  71  49  61  43 / 100  10  80  10
CTB  67  48  61  42 /  80  50  90   0
HLN  75  50  68  45 /  80   0  30   0
BZN  77  42  68  40 /  80  10  10   0
WYS  70  36  65  35 /  50  10   0   0
DLN  73  41  69  40 /  50   0   0   0
HVR  73  50  63  43 /  90  30  70  10
LWT  73  45  59  38 /  90  10  50  10

&&

.TFX WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$

http://www.weather.gov/greatfalls