195
FXUS65 KCYS 061955
AFDCYS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
155 PM MDT MON JUL 6 2026
KEY MESSAGES
- STRONG TO MARGINALLY SEVERE THUNDERSTORMS POSSIBLE MONDAY
THROUGH THURSDAY.
- A RIDGE BUILDS LATE IN THE LONG TERM, DRYING THE AREA OUT AND
PERHAPS BREAKING HEAT RECORDS.
SHORT TERM /THROUGH WEDNESDAY/
ISSUED AT 152 PM MDT MON JUL 6 2026
A FEW STORMS ARE BEGINNING TO APPEAR ON RADAR EARLY THIS AFTERNOON
OVER THE HIGH TERRAIN. STORMS ARE CURRENTLY PULSEY AS THERE IS VERY
LITTLE SHEAR IN THE ENVIRONMENT TO SUSTAIN THEM AS PER MODEL
SOUNDINGS. AS THE AFTERNOON PROGRESSES, NO ORGANIZED CONVECTION IS
ANTICIPATED AS SHEAR REMAINS QUITE WEAK WITH RATHER UNIMPRESSIVE
INSTABILITY. REGARDLESS OF THE UNFAVORABLE ENVIRONMENT, HI-RES
GUIDANCE STILL HAS SHOWERS AND STORMS DEVELOPING OFF THE HIGH
TERRAIN AND PROGRESSING EASTWARD THROUGH THE AFTERNOON AND EVENING
HOURS. CANNOT RULE OUT A FEW ISOLATED SEVERE GUSTS IN ANY SHOWERS
AND STORMS GIVEN THE EXTREMELY DRY LOW-LEVELS. MODEL SOUNDINGS SHOW
STRONG INVERTED-V PROFILES, LEADING TO IMPRESSIVE DCAPE VALUES AS
HIGH AS 1600 J/KG. MUCAPE VALUES ARE ALSO HIGH ENOUGH TO SEE
SOME SMALL HAIL IN STORMS. THE OTHER CONCERN GIVEN THE DRY LOW-
LEVELS IS DRY LIGHTNING. WITH RELATIVE HUMIDITY VALUES IN THE
TEENS ACROSS MUCH OF THE AREA AND HIGH CLOUD BASES, LITTLE, IF
ANY, PRECIPITATION WILL MAKE IT TO THE GROUND IN THESE STORMS.
THEREFORE, FIRE STARTS CANNOT BE RULED OUT WITH DRY LIGHTNING.
STORMS WILL DISSIPATE AND MOVE OUT OF THE AREA BY MIDNIGHT
TONIGHT.
TUESDAY WILL BE ALMOST A CARBON COPY TO TODAY AS UPPER-LEVEL RIDGING
CONTINUES OVER THE ROCKIES. THE RIDGE WILL LEAD TO ANOTHER HOT DAY
WITH 700 MB TEMPERATURES IN THE UPPER TEENS. HIGHS WILL RANGE FROM
THE UPPER 80S OUT WEST, TO 90S AND LOW 100S EAST OF THE LARAMIE
RANGE. YET ANOTHER WEAK DISTURBANCE WILL PASS THROUGH THE RIDGE ON
TUESDAY, LEADING TO STORM CHANCES DURING THE AFTERNOON AND EVENING
HOURS. THE DISTURBANCE WILL SPIKE MID-LEVEL MOISTURE A BIT MORE THAN
MONDAY, LEADING TO GREATER COVERAGE OF STORMS. THE ENVIRONMENT WILL
BE SLIGHTLY MORE FAVORABLE FOR STRONGER STORMS WITH A BIT BETTER
SHEAR AND CAPE VALUES. THREATS WILL BE THE SAME AS TODAY, WITH
PRIMARILY A SEVERE WIND CONCERN WITH DRY LOW-LEVELS AND DCAPE VALUES
AROUND 1000 J/KG. MUCAPE VALUES WILL ALSO BE AROUND 1000 J/KG SO
ISOLATED LARGE HAIL WILL ALSO BE POSSIBLE WITH STORMS. HI-RES
GUIDANCE SHOWS LINGERING SHOWERS AND STORMS THROUGH MUCH OF THE
OVERNIGHT AS THE DISTURBANCE IS SLOW TO MOVE OUT OF THE AREA.
FLOW WILL TURN MORE ZONAL ON WEDNESDAY, FLATTENING OUT THE RIDGE AND
COOLING TEMPERATURES OFF ABOUT 5 TO 10 DEGREES. A WEAK DISTURBANCE
MOVING ACROSS WYOMING WILL RESULT IN ANOTHER ROUND OF AFTERNOON AND
EVENING THUNDERSTORMS. THE ENVIRONMENT ON WEDNESDAY LOOKS MORE
FAVORABLE THAN MONDAY AND TUESDAY FOR SEVERE STORMS, WITH THE BEST
SHEAR AND INSTABILITY SEEN THIS WEEK. THIS WILL ONCE AGAIN LEAD TO
BOTH A SEVERE WIND AND HAIL THREAT, MAINLY EAST OF THE LARAMIE
RANGE.
LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/
ISSUED AT 152 PM MDT MON JUL 6 2026
AFTERNOON THUNDERSTORMS SHOULD BE ONGOING THROUGH THE FIRST COUPLE
OF HOURS OF WEDNESDAY NIGHT. THIS ACTIVITY SHOULD TAPPER OFF BEFORE
MIDNIGHT LEAVING FOR A CLOUD FILLED AND MUGGY NIGHT. SOME FOG COULD
BE POSSIBLE IN PORTIONS OF THE NEBRASKA PANHANDLE.
THURSDAY WILL BE THE LAST DAY IN A STRETCH FOR MILD AFTERNOON
TEMPERATURES. THE REMAINDER OF THE MONSOON MOISTURE AND UPPER LEVEL
LIFTING WILL KEEP THE WEATHER INTERESTING, SOMETHING THAT CANNOT BE
SAID FOR LATER ON. AFTERNOON HIGHS ARE LIKELY TO STAY BELOW 90. WE
WILL NEED TO WATCH THE WESTERN MOST COUNTIES FOR ELEVATED FIRE
CONDITIONS. MINIMUM RELATIVE HUMIDITY VALUES WILL BOTTOM OUT IN THE
MID TO LOWER TEENS FOR PORTIONS OF CARBON, ALBANY, AND CONVERSE
COUNTIES. WINDS LOOK TO BE JUST BELOW RED FLAG CRITERIA AT THIS TIME
HOWEVER. AFTERNOON THUNDERSTORMS ARE ANTICIPATED ALONG I-25 WHERE
MUCAPE VALUES OF AROUND 2000 J/KG AND BULK WIND SHEAR OF 30-40 KNOTS
COULD SUPPORT SOME ORGANIZED THUNDERSTORMS. THE SUB CLOUD LAYER MAY
NOT BE AS DRY AS IT HAS BEEN DURING THE PREVIOUS DAYS ALLOWING FOR
MORE RAINFALL FROM STORMS ALONG WITH SEVERE WEATHER POTENTIAL.
PAST THURSDAY AND THROUGH AT LEAST MONDAY THE UPPER LEVEL RIDGE
BUILDS WITH FORCE AND SUBSIDING AIR STARTS DRYING AND HEATING THE
AREA. A LARGE PORTION OF THE NEBRASKA PANHANDLE WILL SEE +100 DEGREE
AFTERNOONS WHILE THE INNER BASINS SEE 90S. THE GFS HAS BEEN SHOWING
SOME RATHER HOT TEMPERATURES THE LAST FEW DAYS, HOWEVER RUNS
RECENTLY ARE TRENDING DOWN THANKFULLY. THE GFS DOES HAVE A WARM BIAS
AT LONGER RANGES. THAT BEING SAID MODEL BLENDS ARE STILL HOT AND IF
THE RIDGE CENTER SLIDES EAST OF OUR AREA, DOWNSLOPING EFFECTS CAN
CAUSE TEMPERATURES LEE SIDE OF RIDGES TO HEAT A FEW DEGREES ON TOP
OF EXPECTED TEMPERATURES.
LETS TALK ABOUT THE FIRE WEATHER OUTLOOK. NATURALLY THIS SUBSIDING
AIR ALSO DRIES THE ENVIRONMENT EFFICIENTLY AND FORECASTS HAVE
AFTERNOON MINIMUM RELATIVE HUMIDITIES IN THE TEENS AND SINGLE
DIGITS. BEING DIRECTLY UNDERNEATH OF SUCH A STRONG RIDGE DOES HAVE A
PERK, THE WINDS ARE TYPICALLY LESSENED. WE WILL LIKELY STILL SEE 25-
35 MPH WIND GUST DURING THIS PERIOD, BUT CONSISTENT WINDS ABOVE 25
MPH MAY BE DIFFICULT TO ACHIEVE. REGARDLESS, THE ANTECEDENT
CONDITIONS AND CRITICAL FUELS COULD LEAD TO US HAVING AFTERNOON
CRITICAL FIRE CONDITIONS THROUGH MUCH OF THE RIDGING PATTERN
DAYS.
AVIATION /18Z TAFS THROUGH 18Z TUESDAY/
ISSUED AT 1143 AM MDT MON JUL 6 2026
MOST TERMINALS WILL EXPERIENCE VFR CONDITIONS THROUGH THIS
AFTERNOON. A COMPLEX OF THUNDERSTORMS AND SHOWERS ARE EXPECTED
TO DEVELOP NEAR THE LARAMIE RANGES AND ALONG THE BOUNDARY OF
THIS MORNINGS SHOWERS AND THUNDERSTORMS JUST NORTH OF THE
NEBRASKA PANHANDLE. THESE STORMS COULD IMPACT TERMINALS THROUGH
THE EARLY EVENING WITH THE MAIN HAZARDS BEING REDUCED
VISIBILITIES FROM HEAVY RAIN AND BLOWING DUST ALONG WITH STRONG
DOWNBURST WINDS, POSSIBLY TO 40-45 KNOTS, AND LIGHTNING.
THEREFORE, PROB30 GROUPS ARE MAINTAINED FOR AIRPORTS WITH THE
GREATEST CHANCES OF STORMS. WINDS WILL BE VARIABLE AT TIMES
OUTSIDE OF STORM CORES AND COULD HAVE LONG DISTANCE INFLUENCES.
TOMORROW MORNING CONTINUES VFR CONDITIONS. WINDS IN THE NEBRASKA
PANHANDLE PICK UP FROM A LOW LEVEL JET WITH GUSTS TO 30 KNOTS
POSSIBLE OUT OF THE SOUTH. BEFORE THE JET REACHES THE SURFACE,
THERE IS A SLIGHT RISK OF LOW LEVEL WIND SHEAR OVER KBFF FROM
08-11Z.
CYS WATCHES/WARNINGS/ADVISORIES
WY...NONE.
NE...NONE.
SHORT TERM...SF
LONG TERM...RV
AVIATION...RV
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