A series of Pacific storms moved across the region in May and occasionally absorbed remnants of tropical moisture which produced significant precipitation over the area. As a result, drought conditions across western Colorado improved dramatically by the end of the month.
Every event with a place to put it; 14 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.
A series of Pacific storms moved across the region in May and occasionally absorbed remnants of tropical moisture which produced significant precipitation over the area. As a result, drought conditions across western Colorado improved dramatically by the end of the month.
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, 11:15 PM MST, 45 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAND JUNCTION CO 1215 AM MDT FRI MAY 1 2015 .SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT) ISSUED AT 254 PM MDT THU APR 30 2015 A STREAM OF MID-LEVEL MOISTURE SEEN ON WATER VAPOR SATELLITE IS REACHING INTO CENTRAL COLORADO AND FIRING OFF SHOWERS AND THUNDERSTORMS ALONG A SOUTHWEST TO NORTHEAST AXIS ACROSS UTAH AND NORTHWEST COLORADO. THIS STREAM OF MOISTURE WILL CONTINUE TO MOVE THROUGH THE AREA CLOCKWISE AROUND THE HIGH PRESSURE ALOFT. A SLIGHT WIND SHIFT FROM WESTERLY TO NORTHERLY WINDS WILL OCCUR THIS EVENING. WITHOUT DAYTIME HEATING AFTER SUNSET...SHOWERS WILL TAPER OFF OVERNIGHT. FRIDAY WILL BE ANOTHER DAY OF DIURNAL SHOWERS BEING INITIATED BY TOPOGRAPHIC INFLUENCE AND WEAK PIECES OF ENERGY UNDERNEATH THE PREVAILING HIGH PRESSURE PATTERN. A SPIKE IN PRECIPITABLE WATER VALUES TOMORROW WILL RAISE RELATIVE HUMIDITY FOR TOMORROW...MAKING IT A BIT EASIER TO INITIATE SHOWERS IN THE LATE MORNING AND EARLY AFTERNOON. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 254 PM MDT THU APR 30 2015 DIURNAL TERRAIN DRIVEN SHOWERS AND THUNDERSTORMS ARE EXPECTED ON SATURDAY AS HIGH PRESSURE REMAINS OVER UTAH AND COLORADO. AS THIS HIGH PRESSURE DRIFTS EAST SUNDAY...A H5 VORT MAXIMA WILL SWING BY THE UT/WY/CO BORDER SUNDAY MORNING CREATING A GREATER CHANCE OF PRECIPITATION OVER NE UTAH AND NW COLORADO SUNDAY AFTERNOON. A LOW PRESSURE SYSTEM CROSSING OVER SOCAL AND NORTHERN BAJA CA ON MONDAY WILL HEAD TOWARD THE FOUR CORNERS BY TUESDAY. HOWEVER...THE NEWEST 12Z MODEL RUNS HAVE SHIFTED THE PASSAGE OF THIS FEATURE THROUGH COLORADO MUCH FURTHER EAST. IF THE LOW PRESSURE CENTER HEADS FURTHER EAST...THEN MOST OF THE ACTIVITY WILL SHIFT TO THE FRONT RANGE AND ALONG THE DIVIDE. UNCERTAINTY DEFINITELY EXISTS MID TO LATE NEXT WEEK BUT CONFIDENCE IS GOOD ON AN ACTIVE WEATHER PATTERN CONTINUING. TEMPERATURES WILL COOL OFF MIDWEEK TO NEAR NORMAL THEN POTENTIALLY DROP BELOW NORMAL TOWARD THE END OF THE WEEK AS COOLER AIR FROM THE PACIFIC NORTHWEST SETTLES INTO THE REGION. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 1215 PM MDT THU APR 30 2015 SHALLOW COLD FRONT PUSHES INTO THE ERN UINTA BASIN AND NW COLORADO WITH WIND SHIFTS FROM THE N-NE. ISOLATED GUSTS TO 25 MPH WILL BE POSSIBLE UNTIL ABOUT 09Z. NO AVIATION WEATHER HAZARDS EXPECTED BETWEEN 09Z-19Z FRIDAY WITH VFR PREVAILING. AFTER 19Z...SCATTERED -SHRA/-TSRA WILL BE DEVELOPING ALONG THE HIGH TERRAIN. BY LATE IN THE DAY...ISOLATED CONVECTIVE MAY DRIFT OVER THE ADJACENT LOWER VALLEYS. ELEVATED TAF SITES SUCH AS KASE...KEGE...KTEX COULD OBSERVE A BRIEF SHOWER OR THUNDERSTORM WITH GUSTY WINDS. -TSRA COULD BE IN THE VICINITY OF KGJT...KRIL...AND KMTJ BETWEEN 21Z-02Z. AFTER 02Z...CONVECTION DISSIPATES FOR THE DAY. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...NONE. UT...NONE. && SHORT TERM...JAM LONG TERM...JAM AVIATION...PF
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
The national radar mosaic for the moment the first event began.
14 drought. Local standard time, as filed.
Monthly precipitation totals of 2 to 3 times above normal improved drought conditions from the severe category to the moderate category by the end of the month.
Monthly precipitation totals of 2 to 3 times above normal improved drought conditions from the severe category to the moderate category by the end of the month.
Monthly precipitation totals of 2 to 3 times above normal improved drought conditions from the severe category to the moderate category by the end of the month.
Monthly precipitation totals of 2 to 3 times above normal improved drought conditions from the severe category to the moderate category by the end of the month.
Monthly precipitation totals of 2 to 3 times above normal improved drought conditions from the severe category in the southern portion of the zone to the moderate category by the end of the month. The northern portion of the zone improved from moderate drought conditions to the abnormally dry category by the end of the month.
Monthly precipitation totals of 2 to 3 times above normal improved drought conditions from the severe category to the moderate category by the end of the month.
Monthly precipitation totals of 2 to 3 times above normal improved drought conditions from the severe category to the moderate or better categories by the end of the month.
Monthly precipitation totals of 2 to 3 times above normal improved drought conditions from the severe category to the abnormally dry category by the end of the month.
Monthly precipitation totals of 2 to 3 times above normal improved drought conditions from the moderate to severe categories to the abnormally dry category by the end of the month.
Monthly precipitation totals of 2 to 3 times above normal improved drought conditions from the severe category to the abnormally dry category by the end of the month.
Monthly precipitation totals of 2 to 3 times above normal improved drought conditions from the severe category to the abnormally dry category by the end of the month.
Monthly precipitation totals of 2 to 3 times above normal improved drought conditions from the severe category to the abnormally dry category by the end of the month.
Monthly precipitation totals of 2 to 3 times above normal improved drought conditions from the severe category in the western portion of the zone to the moderate category by the end of the month. The eastern portion of the zone improved from moderate drought conditions to the abnormally dry category by the end of the month.
Monthly precipitation totals of 2 to 3 times above normal improved drought conditions from the severe category that existed in the western portion of the zone to the abnormally dry category by the end of the month.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Colorado in 2015Every state in 2015This day in weather historyWarnings in Colorado, May 2015
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: 586283, 586284, 586285, 586286, 586287, 586288, 586289, 586290, 586291, 586292, 586293, 591099, 591100, 591102.