April 2007 climate report for Tucson

...APRIL HIGHLIGHTS...
...20TH WARMEST APRIL ON RECORD...
...LIGHTNING STARTS WILDFIRE ON MT. FAGAN ON THE 28TH...
...LONG TERM SEVERE DROUGHT CONDITIONS CONTINUES...

THREE WEATHER PERSONALITIES PREVAILED DURING APRIL 2007. THEY WERE:
1) MUCH ABOVE NORMAL TEMPERATURES
2) BELOW NORMAL TEMPERATURES...WINDY CONDITIONS AND SOME RAIN
3) ABOVE NORMAL TEMPERATURES...BREEZY CONDITIONS AND SOME RAIN.

THE MONTH STARTED OFF VERY WARM WITH DAYTIME TEMPERATURES BETWEEN THE
1ST AND 11TH IN THE 80S TO LOWER 90S. DAILY LOW TEMPERATURES WERE IN
THE 50S TO MID 60S WITH A RECORD HIGH MINIMUM TEMPERATURE BEING SET
ON THE 8TH OF 65 DEGREES. DAILY AVERAGE TEMPERATURES WERE 5 TO 13
DEGREES ABOVE NORMAL.

DURING THE NEXT TWO WEEKS (12TH THRU 24TH)...SOUTHEAST ARIZONA WAS IN
AN ACTIVE WEATHER PATTERN WHERE THREE STORM SYSTEMS MOVED THROUGH THE
AREA WITH WIND AND SOME RAIN. DAILY AVERAGE TEMPERATURES WERE 1 TO 10
DEGREES BELOW NORMAL WITH DAYTIME HIGHS BEING ON A ROLLER COASTER.

THE FIRST STORM AFFECTED THE AREA ON THE 12TH AND 13TH AND BROUGHT
SOME LIGHT RAIN ALONG WITH WIND GUSTS BETWEEN 40 AND 50 MPH. RAINFALL
AMOUNTS ACROSS THE METRO AREA GENERALLY RANGED BETWEEN A TENTH TO A
THIRD OF AN INCH WITH A FEW SPOTS NEAR THE SURROUNDING MOUNTAINS
RECORDING AROUND A HALF AN INCH.

THE SECOND STORM SYSTEM MOVED THROUGH THE AREA ON THE 15TH WITH WIND
GUSTS BETWEEN 35 AND 45 MPH. HOWEVER NO RAIN WAS ASSOCIATED WITH THIS
SYSTEM.

HIGH PRESSURE BUILT OVER THE AREA BETWEEN THE 18TH AND 20TH BEFORE
A THIRD STORM SYSTEM AFFECTED THE AREA ON THE 21ST. THIS STORM
BROUGHT VERY WINDY CONDITIONS TO THE AREA WITH WIND GUSTS BETWEEN 40
AND 50 MPH BEING RECORDED. RAIN FELL DURING THE MORNING HOURS OF THE
21ST WITH TOTALS GENERALLY BETWEEN FIVE-HUNDREDTHS TO A QUARTER OF AN
INCH WITH HIGHER TOTALS IN THE SURROUNDING MOUNTAINS.

THE LAST SIX DAYS OF THE MONTH SAW DAYTIME TEMPERATURES WARMING INTO
THE UPPER 80S AND LOWER 90S. THE LAST STORM SYSTEM OF MONTH AFFECTED
THE AREA ON THE 28TH AS A CLOSED LOW MOVED THROUGH SONORA MEXICO.
THIS FEATURE PICKED UP SOME MOISTURE OVER NORTHERN MEXICO AND SPREAD
IT ACROSS SOUTHEAST ARIZONA. SHOWERS AND ISOLATED THUNDERSTORMS
RAPIDLY MOVED THROUGH THE AREA. RAINFALL AMOUNTS WITH THIS SYSTEM WAS
GENERALLY LESS THAN A TENTH OF AN INCH BUT A FEW SPOTS IN NORTHWEST
TUCSON RECORDED UP TO A QUARTER OF AN INCH. A LIGHTNING STRIKE ON
MOUNT FAGAN STARTED A WILDFIRE WHERE UP TO 550 ACRES WAS BURNED BY
THE 30TH.

OVERALL...THE AVERAGE MONTHLY TEMPERATURE OF 68.6 DEGREES WAS 2.6
DEGREES ABOVE NORMAL AND RANKS AS THE 20TH WARMEST APRIL ON RECORD.
EXTREMES FOR THE MONTH RANGED FROM A HIGH OF 93 DEGREES ON THE 28TH
TO A LOW OF 44 DEGREES ON THE 17TH. MONTHLY RAINFALL TOTALS ACROSS
THE METRO AREA RANGED FROM A TENTH OF AN INCH TO A HALF AN INCH WITH
UP TO AN INCH IN THE SURROUNDING MOUNTAINS. THE INTERNATIONAL AIRPORT
OFFICIALLY RECORDED FIFTEEN HUNDREDTHS OF AN INCH WITH NORMAL BEING
JUST UNDER THREE TENTHS OF AN INCH.

APRIL RAINFALL TOTALS OVER THE PAST 10 YEARS...
2007 ... 0.15"          2002 ... 0.00"
2006 ... TRACE          2001 ... 0.84"
2005 ... 0.33"          2000 ... TRACE
2004 ... 1.05"          1999 ... 1.34"
2003 ... 0.04"          1998 ... 0.39"
10 YEAR AVERAGE - 0.41"  1971-2000 NORMAL - 0.28"

...APRIL 2007 STATS...         MONTH     NORMAL     DEPARTURE
AVERAGE HIGH TEMPERATURE        83.3      81.5        + 1.8
AVERAGE LOW  TEMPERATURE        53.8      50.5        + 3.3
AVERAGE TEMPERATURE             68.6      66.0        + 2.6
RAINFALL                        0.15"     0.28"      - 0.13"

THE AIRPORT HAS ONLY RECORDED AN INCH AND A HALF /1.49"/ OF RAIN
DURING THE FIRST FOUR MONTHS OF 2007. THIS RANKS AS THE 25TH DRIEST
FIRST FOUR MONTHS ON RECORD. THE RECORD IS ONE-HUNDREDTH OF AN INCH
/0.01"/ WHICH OCCURRED IN 1972.

JAN 1ST TO APRIL 30TH RAINFALL TOTALS OVER THE PAST 10 YEARS...
2007 ... 1.49"          2002 ... 0.68"
2006 ... 0.41"          2001 ... 3.42"
2005 ... 3.32"          2000 ... 1.22"
2004 ... 3.42"          1999 ... 1.35"
2003 ... 1.65"          1998 ... 5.40"
10 YEAR AVERAGE - 2.24"  1971-2000 NORMAL - 2.96"

...2007 STATS THRU APRIL...     YEAR     NORMAL     DEPARTURE
AVERAGE HIGH TEMPERATURE        73.0      71.9        + 1.1
AVERAGE LOW  TEMPERATURE        44.8      44.0        + 0.8
AVERAGE TEMPERATURE             58.9      58.0        + 0.9
RAINFALL                        1.49"     2.96"      - 1.47"
WATER YEAR RAINFALL (OCT-APR)   2.38"     5.87"      - 3.49"

2006-2007 WATER YEAR RAINFALL TOTAL THROUGH THE END OF APRIL RANKS
AS THE 13TH DRIEST ON RECORD WITH UNDER TWO AND A HALF INCHED BEING
RECORDED AT THE AIRPORT. THIS IS THREE AND A HALF INCHES BELOW
NORMAL AND WITH FIVE MONTHS LEFT IN THE CURRENT WATER YEAR PERIOD
THE PROSPECTS OF HAVING A NORMAL WATER YEAR LOOKS RATHER GRIM. THE
AIRPORT WILL HAVE TO RECORD 9.79 INCHES OR MORE FROM MAY 1ST THRU
SEPTEMBER 30TH FOR THE WATER YEAR TO BE AT THE NORMAL TOTAL OF
12.17". LOOKING BACK AT THE HISTORICAL RECORD...THIS HAS HAPPENED
ONLY EIGHT TIMES IN THE PAST 113 YEARS...OR 7 PERCENT OF THE TIME.

WATER YEAR RAINFALL TOTALS OVER THE PAST 10 YEARS...
2006-2007 ... 2.38"          2001-2002 ... 2.02"
2005-2006 ... 0.73"          2000-2001 ... 9.77"
2004-2005 ... 5.09"          1999-2000 ... 1.22"
2003-2004 ... 4.99"          1998-1999 ... 2.71"
2002-2003 ... 3.02"          1997-1998 ... 9.15"
10 YEAR AVERAGE - 4.11"  1971-2000 NORMAL - 5.87"

DUE TO THE EXTENDED DRY PERIOD SINCE LAST SEPTEMBER...PIMA COUNTY
DECLARED A STAGE 1 DROUGHT. THIS MEANS THAT ALL PERSONS ARE ASKED TO
IMPLEMENT VOLUNTARY REDUCTIONS IN WATER USE.
		                                           
...LOOKING AHEAD INTO MAY...
THE CLIMATE PREDICTION CENTER FORECASTS THAT THE MONTH OF MAY WILL
HAVE EQUAL CHANCES OF ABOVE...NORMAL...OR BELOW NORMAL TEMPERATURES
AND RAINFALL.

AVERAGE HIGH TEMPERATURE ......... 90.4 DEGREES
AVERAGE LOW TEMPERATURE .......... 58.6 DEGREES
AVERAGE MONTHLY TEMPERATURE ...... 74.5 DEGREES
RECORD HIGH TEMPERATURE .......... 111 DEGREES ON MAY 29 1910
RECORD LOW TEMPERATURE ........... 32 DEGREES ON MAY 3 1899
WARMEST MAY (AVG) ................ 80.2 DEGREES IN 2000
COLDEST MAY (AVG) ................ 64.6 DEGREES IN 1905
NORMAL RAINFALL .................. 0.24 INCHES
WETTEST MAY DAY .................. 1.34 INCHES ON MAY 15 1931
WETTEST MAY ...................... 1.34 INCHES IN 1931
DRIEST MAY ....................... 0.00 INCHES IN 2002
                                     (LAST OF 22 OCCURRENCES)

THE NUMBER OF DAYLIGHT HOURS INCREASES FROM 13 HOURS 26 MINUTES ON
THE 1ST TO 14 HOURS 7 MINUTES ON THE 31ST...A GAIN OF 41 MINUTES. 

GLUECK