723
FXUS65 KCYS 181802
AFDCYS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
1202 PM MDT SAT JUL 18 2026
KEY MESSAGES
- HOT, DRY, AND BREEZY CONDITIONS CONTINUE THROUGH SUNDAY BEFORE
A MUCH AWAITED COLD FRONT ARRIVES FOR THE START OF THE WEEK.
- MONSOONAL MOISTURE WILL ATTEMPT TO RETURN AS EARLY AS MONDAY,
LEADING TO INCREASED PRECIPITATION CHANCES THROUGH MUCH OF
NEXT WEEK.
SHORT TERM /THROUGH MONDAY/
ISSUED AT 253 AM MDT SAT JUL 18 2026
WITH THE UPPER-LEVEL RIDGE STILL FIRMLY IN PLACE OVER WYOMING, HOT
AND DRY CONDITIONS ARE EXPECTED TO CONTINUE INTO THE DAY SATURDAY.
MOSTLY SUNNY SKIES ACROSS A MAJORITY OF THE CWA WILL HELP
TEMPERATURES CLIMB ABOUT 5 DEGREES ABOVE NORMAL FOR THIS TIME OF
YEAR. MOST LOCATIONS WILL SEE HIGH TEMPERATURES IN THE 90S, BUT
WOULD NOT BE SURPRISED TO SEE A FEW LOWER ELEVATION SPOTS REACH THE
LOW 100S. SOME MOISTURE WILL BE PRESENT IN WESTERN WYOMING AS THE
MONSOON STRENGTHENS OVER THE DESERT SOUTHWEST AND PUSHES NORTHWARD.
THE WESTERN PORTION OF THE CWA WILL BE ON THE EASTERN EDGE OF THE
MONSOON PUSH, SO IT IS POSSIBLE THAT A FEW SHOWERS OR THUNDERSTORMS
COULD DEVELOP WEST OF THE LARAMIE RANGE DURING THE AFTERNOON HOURS.
HI-RES GUIDANCE SHOWS STORMS INITIALLY FORMING OVER THE HIGH TERRAIN
OF THE SNOWY AND SIERRA MADRE RANGES BEFORE PUSHING NORTH THROUGHOUT
THE EVENING. STORMS WILL DISSIPATE BY ABOUT MIDNIGHT, WITH THE REST
OF THE NIGHT EXPECTED TO BE QUIET.
SUNDAY WILL BE VIRTUALLY THE SAME AS SATURDAY WITH HOT TEMPERATURES
CONTINUING AND ANOTHER CHANCE OF SHOWERS AND STORMS. HIGHS EAST
OF THE LARAMIE RANGE ON SUNDAY WILL BE ABOUT 5 DEGREES WARMER
COMPARED TO SATURDAY, PROMPTING A HEAT ADVISORY FOR MOST OF THE
AFOREMENTIONED AREA. THERE WILL BE A LITTLE LESS MOISTURE
AROUND ON SUNDAY, HOWEVER, HI-RES GUIDANCE STILL SHOWS THE
POTENTIAL FOR A FEW STORMS DEVELOPING OFF THE HIGH TERRAIN AND
MOVING INTO THE PLAINS THROUGH THE AFTERNOON HOURS. GIVEN THAT
LESS MOISTURE IS PRESENT, SHOWERS AND STORMS WILL LIKELY END
AROUND SUNSET.
LONG TERM /MONDAY NIGHT THROUGH FRIDAY/
ISSUED AT 220 PM MDT FRI JUL 17 2026
MONDAY...MONSOONAL MOISTURE AT LOW AND MID LEVELS INCREASES FURTHER,
AIDING IN ANOTHER INCREASE IN LATE DAY SHOWER AND THUNDERSTORM
COVERAGE, AND BENEFICIAL RAINS, WITH COVERAGE INCREASING TO
SCATTERED 30 TO 60 PERCENT POPS, PROBABILITY OF MEASURABLE
PRECIPITATION, WITH THE GREATEST COVERAGE OVER AND NEAR OUR MOUNTAIN
ZONES.
TUESDAY-FRIDAY...A RELATIVELY SIGNIFICANT PATTERN CHANGE WILL OCCUR,
WITH "BEWARE" NORTHWEST FLOW ALOFT DEVELOPING ALONG WITH A DECENT
INCREASE IN LOW AND MID LEVEL MOISTURE AND UPSLOPE SOUTHEAST
MECHANICAL LIFT AT LOW LEVELS, AND OCCASIONAL PASSING SHORTWAVE
TROUGHS ALOFT, HELPING TO PRODUCE SCATTERED TO NUMEROUS SHOWERS, AND
SCATTERED THUNDERSTORMS IN THE AFTERNOONS AND EVENINGS, WITH
BENEFICIAL RAINFALL AND POSSIBLY SOME LOCALLY HEAVY RAINS FROM SOME
OF THE SLOWER MOVING THUNDERSTORMS. THE MOST LIKELY LOCATIONS FOR
LOCALLY HEAVY RAIN AND THE GREATEST AREAL COVERAGE MAY BE ALONG AND
EAST OF INTERSTATE 25. ON FRIDAY, THE GFS PROGS THE LAST OF THE
PASSING SHORTWAVE TROUGHS ALOFT TO MOVE INTO NEBRASKA BY EVENING,
WITH SHORTWAVE RIDGING ALOFT BULGING ACROSS WYOMING, THUS EXPECT AN
ATTENDANT DECREASE IN AREAL AFTERNOON AND EVENING SHOWER AND
THUNDERSTORM COVERAGE.
AVIATION /18Z TAFS THROUGH 18Z SUNDAY/
ISSUED AT 1125 AM MDT SAT JUL 18 2026
STRONG RIDGING ALOFT WILL CONTINUE. EXPECT SOME HIGH BASED
CUMULUS FORMATION THIS AFTERNOON AND THIS EVENING, MAINLY WEST
OF I-25 IN A LOW AND MID LEVEL THETA-E RIDGE AXIS, WITH A FEW
SHOWERS OR WEAK HIGH BASED THUNDERSTORMS POSSIBLE AT THE KRWL
SITE FROM 21Z TO 03Z. VFR PREVAILS. TYPICAL GUSTY MIX DOWN AND
GRADIENT WINDS EXPECTED UNTIL SUNSET.
CYS WATCHES/WARNINGS/ADVISORIES
WY...HEAT ADVISORY FROM NOON SUNDAY TO 6 PM MDT MONDAY FOR WYZ101-
102-108.
NE...HEAT ADVISORY UNTIL 6 PM MDT MONDAY FOR NEZ002-095.
HEAT ADVISORY FROM NOON SUNDAY TO 6 PM MDT MONDAY FOR NEZ003-
019>021-096.
SHORT TERM...SF
LONG TERM...RUBIN
AVIATION...RUBIN
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