Skip Navigation Linkswww.weather.gov 
NOAA logo - Click to go to the NOAA homepage National Weather Service Forecast Office   NWS logo - Click to go to the NWS homepage    
Great Falls, Montana
navigation bar decoration      
spacer
ANNUAL CLIMATIC SUMMARY FOR HELENA
NATIONAL WEATHER SERVICE GREAT FALLS MT
1122 PM MST SUN DEC 31 2000

ANNUAL WEATHER SUMMARY FOR HELENA FOR 2000.

AVERAGE TEMPERATURE..................:  44.8
DEPARTURE FROM NORMAL................:  +0.8
HIGHEST TEMPERATURE..................:  101 ON JULY 30TH
LOWEST TEMPERATURE...................:  -18 ON DECEMBER 16TH

TOTAL PRECIPITATION (INCHES).........:   8.74    ...14TH DRIEST...                     
DEPARTURE FROM NORMAL................:  -2.86
GREATEST IN 24 HOURS.................:   1.01 ON OCTOBER 11TH-12TH

THE YEAR IN HELENA WILL BE REMEMBERED FOR BEING DRY AND MARRED BY POOR 
AIR QUALITY DURING THE LATE SUMMER. EVERY MONTH EXCEPT OCTOBER HAD 
BELOW NORMAL PRECIPITATION. ALTHOUGH THE SUMMER MONTHS WERE HOTTER THAN 
USUAL...COLDER THAN NORMAL PERIODS IN THE SPRING AND FALL PUT THE 
YEARLY AVERAGE TEMPERATURE NEAR NORMAL.

MEMORABLE WEATHER EVENTS DURING 2000 IN HELENA...

THE YEAR BEGAN WITH MILD CONDITIONS FOR THE SEASON. THE ONLY TIME THE 
TEMPERATURE DIPPED BELOW ZERO IN THE MONTH WAS FOR A COUPLE OF HOURS ON 
THE MORNING OF THE 3RD. A RARE TASTE OF A TYPICAL WINTER BEGAN ON 
FEBRUARY 9TH AS A CANADIAN AIR MASS MOVED IN. TEMPERATURES STAYED BELOW 
FREEZING UNTIL THE 18TH. ACCUMULATING SNOW FELL FOR FIVE CONSECUTIVE 
DAYS STARTING ON THE 10TH WITH THE CITY PICKING UP 5.3 INCHES DURING 
THE PERIOD.

MARCH AND APRIL CONTINUED THE DRY AND MILD START TO THE YEAR. 
TEMPERATURES WERE BELOW NORMAL FOR ONLY 2 DAYS DURING MARCH AND 7 DAYS 
DURING APRIL. BY THE END OF APRIL THE ANNUAL PRECIPITATION DEFICIT WAS 
ALREADY OVER AN INCH. THIS WAS ON THE HEELS OF A FAIRLY DRY 
1999...AND CONCERN ABOUT THE UPCOMING FIRE SEASON WAS ON THE RISE.

MAY IS TYPICALLY THE 2ND WETTEST MONTH IN HELENA...BUT IT QUICKLY 
BECAME A DISAPPOINTMENT IN THE PRECIPITATION DEPARTMENT AS WELL. THE 
MONTH WAS ON THE WAY TO BECOMING ONE OF THE DRIEST IN 
HISTORY...UNTIL A SLUSHY MIX COVERED THE CITY WITH 0.51 INCHES OF  
PRECIPITATION ON THE 31ST. HOWEVER...THE MONTHLY PRECIPITATION WAS 
ALMOST AN INCH BELOW NORMAL.

A COOLER PATTERN SET UP IN THE 2ND WEEK OF JUNE WHEN A NORTHWEST 
FLOW DEVELOPED. SOME RELIEF FROM THE DRY SPELL WAS GRANTED IN THE 
MIDDLE OF THE MONTH AS THUNDERSTORMS DUMPED OVER AN INCH OF RAIN ON 
HELENA BETWEEN THE 15TH AND THE 17TH.

ANOTHER WET PERIOD WAS THE FIRST WEEK OF JULY. COOLER TEMPERATURES 
ALOFT COMBINED WITH WARM MOIST AIR AT THE SURFACE AND TOUCHED OFF A 
DAILY ROUND OF AFTERNOON THUNDERSTORMS BETWEEN THE 1ST AND THE 6TH. 
EAST HELENA WAS PUMMELED WITH GOLF BALL SIZED HAIL ON THE 1ST.

IT THEN RETURNED TO A DRY PATTERN THAT CONTINUED THROUGH THE MIDDLE OF 
SEPTEMBER. BUT UNLIKE THE PREVIOUS MONTHS...THIS DRY SPELL WAS WORSENED 
BY ABOVE NORMAL TEMPERATURES THAT BAKED THE SOIL. THERE WERE 13 DAYS IN 
THE 90S IN JULY AND 11 IN AUGUST. FOR THE YEAR THERE WERE 30 DAYS WITH 
A READING OF 90 OR GREATER...12 MORE THAN NORMAL. THE 101 DEGREES 
RECORDED ON JULY 30TH WAS THE HIGHEST TEMPERATURE IN HELENA SINCE 1990. 
DURING THIS TIME SEVERAL WILDFIRES STARTED AND SMOKY AIR PLAGUED THE 
HELENA VALLEY THROUGH THE MIDDLE OF SEPTEMBER.

ONE OF THE HOTTEST MID-SEPTEMBER DAYS EVER RECORDED IN MONTANA OCCURRED 
ON THE 15TH...WITH HELENA GETTING UP TO A RECORD HIGH 94 DEGREES. BUT 
THEN THE HEAT WAVE CAME TO AN ABRUPT END...AND THE CITY PICKED UP ITS 
FIRST SNOW ON THE 21ST.

A MOIST LOW PRESSURE SYSTEM SET UP OVER WESTERN MONTANA ON OCTOBER 10TH 
TO THE 12TH PROVIDING COPIOUS RAINS WHICH BRIEFLY CHANGED TO SNOW AND 
PUT OUT REMAINING WILDFIRES. HELENA SET AN OCTOBER RECORD WITH 1.01 
INCHES OF PRECIPITATION IN 24 HOURS DURING THIS PERIOD.

A CANADIAN AIR MASS VISITED HELENA ON NOVEMBER 4TH AFTER A COLD FRONT 
PUSHED SOUTH. THE CITY DID NOT SEE ABOVE FREEZING TEMPERATURES BETWEEN 
THE 6TH AND THE 18TH. THIS WAS THE LONGEST PERIOD BELOW FREEZING SO 
EARLY IN THE SEASON. NOVEMBER FINISHED AS THE 4TH COLDEST ON RECORD. 
AFTER 2.5 INCHES OF SNOW ON THE 8TH...SNOW REMAINED ON THE GROUND 
THROUGH THE END OF YEAR. THIS HELPED TO KEEP TEMPERATURES COLDER FOR 
MOST OF THE REMAINING DAYS OF THE YEAR.

ANOTHER CANADIAN PLUNGE GREETED THE CAPITAL CITY ON THE MORNING OF 
DECEMBER 9TH...KEEPING THE CITY WELL BELOW NORMAL FOR THE NEXT WEEK. 
ABOVE NORMAL TEMPERATURES HIT HELENA ON THE LAST WEEK OF THE YEAR WHEN 
THE COLD AIR MASS RETREATED TO EASTERN MONTANA.

A REVIEW OF TEMPERATURE RECORDS SET OR TIED DURING 2000...

DATE    RECORD      VALUE   OLD RECORD    YEAR
FEB 8    HIGH         59        58        1976
MAY 1    HIGH         82        81        1981
JUN 1    LOW          33        33        1979
JUN 5    HIGH         90        88        1969 1977
JUN 7    HIGH         96        94        1985
JUN 8    HIGH         92        91        1996
JUL 29   HIGH         99        99        1934
JUL 30   HIGH        101        98        1988
JUL 31   HIGH         99        98        1908
AUG 1    HIGH         99        98        1908
SEP 15   HIGH         94        89        1953 1979 1998


POMEROY


Webmaster
US Dept of Commerce
National Oceanic and Atmospheric Administration
National Weather Service
Great Falls Weather Forecast Office
5324 Tri-Hill Frontage Rd
Great Falls, MT 59404-4933

Tel: (406) 453-2081

Disclaimer
Information Quality
Credits
Glossary
Organization
Privacy Policy
Freedom of Information Act
About Us
Career Opportunities