Drought conditions through the month of may remained largely unchanged with abnormally dry conditions persisting across much of northwest Colorado. Slight improvement occurred with an area of moderate drought in Routt county being upgraded to abnormally dry.
Every event with a place to put it; 3 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS GJT wrote it up.
Drought conditions through the month of may remained largely unchanged with abnormally dry conditions persisting across much of northwest Colorado. Slight improvement occurred with an area of moderate drought in Routt county being upgraded to abnormally dry.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Grand Junction, CO wrote its last area forecast discussion before the first event at Apr 30, 1:49 PM MST, 10 hours 11 minutes earlier.
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
249 PM MDT FRI APR 30 2010
SHORT TERM...TONIGHT THROUGH SUNDAY...
COOL AND UNSTABLE CONDITIONS WILL PERSIST THROUGH THE WEEKEND AS THE
LARGE-SCALE UPPER TROUGH REMAINS OVER THE REGION. EMBEDDED SHORTWAVE
MOVING S ACROSS WRN CO TODAY PLUS DAYTIME HEATING HELPING TO REALIZE
THAT INSTABILITY IN THE FORM OF SHOWERS. THE SHORTWAVE SHOULD MOVE
OUT OF SW CO THIS EVENING. A BIT OF A LULL EXPECTED SAT WITH
SCATTERED SHOWERS MAINLY OVER THE HIGHER TERRAIN WITH A LACK OF
ORGANIZED FORCING...THEN FINAL SHORTWAVE DROPS SE ACROSS UT LATER
SAT NIGHT AND SUN AND SHOULD ENHANCE SHOWERS AGAIN FOR SUN...SO
WILL BOOST POPS FOR SUNDAY.
TWO TO 3 INCHES OF SNOW OCCURRED ACROSS THE NW VALLEYS EARLIER THIS
MORNING AS THAT SHORTWAVE MOVED FROM WY INTO CO. WILL CONTINUE
THE CURRENT ADVISORY FOR ZONE 2 UNTIL EXPIRATION AT 5 PM TODAY...BUT
SHOWER COVERAGE APPEARS TO BE DECREASING BEHIND THE SHORTWAVE THIS
AFTERNOON. SHOWERS MOVING ACROSS ZONE 8 AS WELL...BUT DO NOT THINK
INTENSITY AND COVERAGE WARRANT CONTINUATION OF A WINTER STORM WARNING
THERE...SO WILL CANCEL IT. OTHERWISE...KEEPING THE CURRENT WINTER
HIGHLIGHTS FOR THE WRN CO MTNS IN PLACE. LOCALLY HIGHER SNOW AMTS
LIKELY IN THE UNCOMPAHGRE GORGE S OF OURAY THAN FOR THE REST OF ZONE
18.
WILL UPGRADE THE FREEZE WATCH TO A FREEZE WARNING FOR TONIGHT AS
PASSAGE OF SHORTWAVE SHOULD PROVIDE FOR SOME WEAK COLD ADVECTION
THOUGH CLOUD COVER WILL LIMIT RADIATIONAL COOLING FOR THE WESTERN CO
VALLEYS. WEAK WARM ADVECTION ALOFT AND INCREASING CLOUDS EXPECTED
SAT NIGHT...BUT WITH BOTH THE MET AND MAV MOS GUIDANCE INDICATING
SUB-FREEZING TEMPS AT RIFLE AND MONTROSE...WENT AHEAD AND ISSUED A
FREEZE WATCH FOR CO ZONES 7 AND 11 FOR SAT NIGHT AS WELL.
.LONG-TERM...SUNDAY NIGHT THROUGH FRIDAY...
THE PATTERN FOR THE LAST MONTH HAS BEEN FOR A TROUGH PASSAGE ONCE A
WEEK. THIS PERSISTENT PATTERN HAS PRODUCED WARMER WINDY WEDNESDAYS AS
IT APPROACHES...THEN COOLER SHOWERS ON THURSDAY-FRIDAY AS IT PASSES.
THE EC HAS BEEN CONSISTENT WITH KEEPING THIS PATTERN FOR AT LEAST
ANOTHER WEEK. THE CANADIAN IS IN GOOD AGREEMENT WITH THE GFS TRYING
TO CATCH UP TO THE EC DEEPER SOLUTION.
SUNDAY NIGHT: THE OPEN TROUGH...ANCHORED WITH AN ALBUQUERQUE LOW...IS
SLIDING EAST LEAVING THE FORECAST AREA IN A DRYING NW FLOW. 500-700MB
WARM ADVECTION LIMITS SHOWERS TO NEAR THE CONTINENTAL DIVIDE WITH
LITTLE OR NO SNOW ACCUMULATION EXPECTED.
MONDAY: WEAK RIDGING IN NW FLOW CONTINUES BRINGS SOME TEMPERATURE
RECOVERY AND DRY CONDITIONS.
TUESDAY-TUESDAY NIGHT: GULF OF ALASKA ENERGY DIGS THROUGH BRITISH
COLUMBIA...BECOMING A CLOSED LOW OVER WASHINGTON-OREGON TUESDAY
NIGHT. POLAR FRONT JET SAGS INTO NORTHERN WYOMING WITH A WEAK
SURFACE COOL FRONT SETTLING ALONG THE COLORADO-WYOMING BORDER. THIS
WILL INCREASE WEST GRADIENT WINDS ACROSS THE REGION WITH A CHANCE OF
SHOWERS ALONG THE NORTHERN BORDER...ESPECIALLY OVER THE EASTERN
UINTA MOUNTAINS.
WEDNESDAY-WEDNESDAY NIGHT: THE UPPER LOW DIGS ACROSS NORTHERN
NV DURING THE DAY THEN EJECTS TOWARDS NW WY OVERNIGHT. THIS IS A
SLIGHTLY DEEPER AND SLOWER TRACK THAN THE 00Z EC RUN. SW GRADIENT
WINDS INCREASE IN THE AFTERNOON FOR THE WARMEST DAY OF THE WEEK. THE
ASSOCIATED COLD FRONT WORKS ACROSS UTAH WEDNESDAY NIGHT KEEPING
OVERNIGHT TEMPERATURES MILD.
THURSDAY-FRIDAY: COLD FRONT SWEEPS OVER THE FORECAST AREA WITH
SHOWERS ALONG AND BEHIND THE FRONT. SHOWERS WILL FAVOR THE NORTH
WITH THE BEST FORCING AND STRONGEST COLD ADVECTION THERE JUST NORTH
OF THE POLAR FRONT JET. -27C COLD CORE REMAINS JUST NORTH OF THE
FORECAST AREA IN THE EC 12Z RUN.
&&
.AVIATION...
WIDESPREAD SHOWERS WILL CONTINUE EAST OF A LINE FROM CRAIG SOUTH
TO CORTEZ COLORADO. MVFR/IFR CIGS AND VSBYS WILL DOMINATE EAST OF
THIS LINE WITH MOUNTAIN TOPS FREQUENTLY OBSCURED. WEST OF THE LINE...
SCATTERED MAINLY MOUNTAIN SHOWERS WILL PRODUCE MVFR LOCAL IFR CIGS
AND VSBYS. SCATTERED SNOW SHOWERS ON SATURDAY WITH VFR VISIBILITY AND
CEILINGS...EXCEPT MVFR/IFR IN SCATTERED SHOWERS MAINLY OVER THE CO
MOUNTAINS.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...FREEZE WARNING FROM MIDNIGHT TONIGHT UNTIL 9 AM MDT SATURDAY
MORNING FOR ZONES 006-007-011.
FREEZE WATCH FROM LATE TONIGHT THROUGH SATURDAY MORNING FOR
ZONES 007-011.
WINTER STORM WARNING UNTIL 6 AM MDT SATURDAY FOR ZONES
004-009-010-012-013.
WINTER WEATHER ADVISORY UNTIL 6 AM MDT SATURDAY FOR ZONES
018-019.
WINTER WEATHER ADVISORY UNTIL 5 PM MDT TODAY FOR ZONE 002.
UT...FREEZE WARNING FROM MIDNIGHT TONIGHT UNTIL 9 AM MDT SATURDAY
MORNING FOR ZONES 022-027-029.
&&
SHORT TERM.....JAD
LONG TERM......JOE
AVIATION.......JOEHAZARDOUS WEATHER OUTLOOK...CORRECTED NATIONAL WEATHER SERVICE GRAND JUNCTION CO 553 AM MDT FRI APR 30 2010 CORRECTED TYPOS IN TEXT COZ001>014-017>023-UTZ022>025-027>029-011200- ANIMAS RIVER BASIN-ARCHES/GRAND FLAT-CANYONLANDS/NATURAL BRIDGES- CENTRAL COLORADO RIVER BASIN- CENTRAL GUNNISON AND UNCOMPAHGRE RIVER BASIN- CENTRAL YAMPA RIVER BASIN-DEBEQUE TO SILT CORRIDOR- EASTERN UINTA BASIN-EASTERN UINTA MOUNTAINS- ELKHEAD AND PARK MOUNTAINS-FLAT TOPS- FOUR CORNERS/UPPER DOLORES RIVER- GORE AND ELK MOUNTAINS/CENTRAL MOUNTAINS-GRAND AND BATTLEMENT MESAS- GRAND VALLEY-LA SAL AND ABAJO MOUNTAINS-LOWER YAMPA RIVER BASIN- NORTHWEST SAN JUAN MOUNTAINS-PARADOX VALLEY/LOWER DOLORES RIVER- ROAN AND TAVAPUTS PLATEAUS-SAN JUAN RIVER BASIN-SOUTHEAST UTAH- SOUTHWEST SAN JUAN MOUNTAINS-TAVAPUTS PLATEAU- UNCOMPAHGRE PLATEAU AND DALLAS DIVIDE-UPPER GUNNISON RIVER VALLEY- UPPER YAMPA RIVER BASIN-WEST ELK AND SAWATCH MOUNTAINS- 553 AM MDT FRI APR 30 2010 ...MOUNTAIN SNOW CONTINUES THROUGH TONIGHT...WITH A CHANCE FOR FREEZING TEMPERATURES AGAIN LATE TONIGHT... THIS HAZARDOUS WEATHER OUTLOOK IS FOR EASTERN UTAH AND WESTERN COLORADO. .DAY ONE...TODAY AND TONIGHT SIGNIFICANT SNOWFALL IS EXPECTED TO CONTINUE OVER THE NORTHERN... CENTRAL...AND SOUTHERN MOUNTAINS TODAY AND TONIGHT AS A STRONG LATE SEASON STORM CONTINUES TO IMPACT THE AREA. AMOUNTS ARE EXPECTED TO RANGE FROM 8 TO 16 INCHES BY EARLY SATURDAY MORNING WITH AMOUNTS APPROACHING 2 FEET ALONG FAVORED WEST FACING SLOPES IN THE NORTH. THE SOUTHERN MOUNTAINS WILL ALSO SEE SOME ACCUMULATING SNOWFALL WITH AMOUNTS RANGING FROM 5 TO 10 INCHES. IN ADDITION...THE CENTRAL COLORADO RIVER VALLEY WILL RECEIVE AN ADDITIONAL 1 TO 3 INCHES OF NEW SNOW BRINGING TOTAL ACCUMULATIONS OF 6 TO 10 INCHES OF TOTAL SNOWFALL BY EARLY SATURDAY MORNING. COLDER AIR FILTERING INTO THE REGION BEHIND THE FRONT ASSOCIATED WITH THIS SYSTEM WILL LIKELY BRING ANOTHER ROUND OF FREEZING TEMPERATURES TO THE REGION. THIS POSES A THREAT TO BUDDING TREES AND OTHER VEGETATION IN THE LOWER VALLEYS. PLEASE SEE THE NATIONAL WEATHER SERVICE GRAND JUNCTION WEB SITE AT HTTP://WEATHER.GOV/GJT FOR ADDITIONAL INFORMATION. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY A CHANCE FOR SNOW WILL CONTINUE...MAINLY OVER THE HIGHER ELEVATIONS INTO EARLY NEXT WEEK...WITH THE NORTHERN AND CENTRAL COLORADO FAVORED. BELOW NORMAL TEMPERATURES WILL ALSO CONTINUE INTO EARLY NEXT WEEK. THE CHANCE FOR PRECIPITATION WILL DIMINISH DURING THE WORK WEEK WITH WARMER TEMPERATURES EXPECTED. .SPOTTER INFORMATION STATEMENT SPOTTER ACTIVATION IS NOT ANTICIPATED TODAY OR TONIGHT...HOWEVER SPOTTERS ARE ENCOURAGE TO REPORT ANY SIGNIFICANT SNOWFALL AMOUNTS. TGJT
The national radar mosaic for the moment the first event began.
3 drought. Local standard time, as filed.
The southern portion of Routt county improved from moderate drought to abnormally dry conditions, while the northern part of Routt county improved to near normal.
The southern portion of the area improved from moderate drought to abnormally dry conditions, while the northern part of the area improved to near normal.
A small portion of the area including San Juan county and the northern part of Archuleta county developed abnormally dry conditions.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Colorado in 2010Every state in 2010This day in weather historyWarnings in Colorado, May 2010
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 243278, 243279, 243286.