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000
CXUS55 KTFX 011639
CLMHLN


CLIMATE REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
712 AM MDT WED MAY 1 2013

...................................

...THE HELENA MT CLIMATE SUMMARY FOR THE MONTH OF APRIL 2013...

CLIMATE NORMAL PERIOD 1981 TO 2010
CLIMATE RECORD PERIOD 1866 TO 2013

WEATHER         OBSERVED          NORMAL  DEPART  LAST YEAR`S
                 VALUE   DATE(S)  VALUE   FROM    VALUE  DATE(S)
                                          NORMAL
................................................................
TEMPERATURE (F)
RECORD
 HIGH              86   04/29/1992
                        04/25/1910
 LOW              -10   04/01/1936
HIGHEST            72   04/27        61      11       83  04/23
LOWEST             16   04/09        28     -12       23  04/03
AVG. MAXIMUM     52.5              57.8    -5.3     61.4
AVG. MINIMUM     29.5              32.1    -2.6     35.6
MEAN             41.0              44.9    -3.9     48.5
DAYS MAX >= 90      0               0.0     0.0        0
DAYS MAX <= 32      1               0.3     0.7        0
DAYS MIN <= 32     18              14.2     3.8       12
DAYS MIN <= 0       0               0.0     0.0        0

PRECIPITATION (INCHES)
RECORD
 MAXIMUM         3.00   1975
 MINIMUM         0.01   1919
TOTALS           0.78              0.98   -0.20     0.59
DAYS >= .01         6               8.7    -2.7
DAYS >= .10         3               3.1    -0.1
DAYS >= .50         0               0.3    -0.3
DAYS >= 1.00        0               0.0     0.0
GREATEST
 24 HR. TOTAL    0.38   04/07 TO 04/07
                        04/06 TO 04/07
                        04/07 TO 04/07

SNOWFALL (INCHES)
RECORDS
 TOTAL             MM   5
 24 HR TOTAL       MM
TOTALS            3.6               3.7    -0.1        T
SINCE 7/1        39.7              37.2     2.5
SNOWDEPTH AVG.      0
DAYS >= TRACE       5               2.9     2.1
DAYS >= 1.0         2               1.3     0.7
GREATEST
 SNOW DEPTH         1   04/22
                        04/21
 24 HR TOTAL      2.0   04/21 TO 04/21

DEGREE_DAYS
HEATING TOTAL     711               602     109      489
 SINCE 7/1       6691              7054    -363     6344
COOLING TOTAL       0                 0       0        0
 SINCE 1/1          0                 0       0        0
.................................................................

WIND (MPH)
AVERAGE WIND SPEED              9.4
HIGHEST WIND SPEED/DIRECTION    43/290    DATE  04/29
HIGHEST GUST SPEED/DIRECTION    58/260    DATE  04/29

SKY COVER
AVERAGE SKY COVER           0.50

AVERAGE RH (PERCENT)     51

WEATHER CONDITIONS. NUMBER OF DAYS WITH
THUNDERSTORM              0     MIXED PRECIP               0
HEAVY RAIN                0     RAIN                       1
LIGHT RAIN                8     FREEZING RAIN              0
LT FREEZING RAIN          0     HAIL                       0
HEAVY SNOW                1     SNOW                       1
LIGHT SNOW               10     SLEET                      0
FOG                       4     FOG W/VIS <= 1/4 MILE      1
HAZE                      4

-  INDICATES NEGATIVE NUMBERS.
R  INDICATES RECORD WAS SET OR TIED.
MM INDICATES DATA IS MISSING.
T  INDICATES TRACE AMOUNT.

&&

SUMMARY...A STRONGER THAN AVERAGE RIDGE OF HIGH PRESSURE OVER THE EASTERN PACIFIC
OCEAN ESTABLISHED A NORTHWESTERLY FLOW ALOFT OVER WESTERN MONTANA. THIS CONFIGURATION
ALLOWED SEVERAL INTRUSTIONS OF COLD CANADIAN AIR MASSES INTO CENTRAL AND EASTERN
MONTANA. AS A RESULT...APRIL 2013 WAS THE 36TH COOLEST MONTH ON RECORD. APRIL 2013
WAS DRIER THAN AVERAGE IN TERMS OF MONTHLY TOTALS FOR PRECIPITATION AND SNOWFALL.
THE PEAK WIND GUST OF 58 MPH ON APRIL 29TH TIED THE APRIL MONTHLY RECORD WHICH
LAST OCCURRED APRIL 11TH 1978.

$$