The Weather Wire

 

August 2009                                                                                                            Volume 17 Number 08

 

Contents

 

 

 
·   Wet Weather Pattern?
 

·   Drought Monitor

 

·   July

    Summary

 

·   July Stats

 

·   August Preview

 

·   Sunrise/Sunset

 

·   Rain Totals

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July

Avg High -84.0

Avg Low - 56.5

Snow - 0.0"

Season Snow - 38.1"

Precipitation - 3.56"

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

August

Avg High - 86.0

Avg Low - 57.4

Avg Snow -  0.0"

Avg Precip - 1.82"

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Skyview Weather 

2350 N Rocky View Rd

Castle Rock, CO 80108

 

Phone: (303) 688-9175

Fax: (303) 380-3338

 

E-mail:    

tim@skyview-wx.com

 

We’re on the Web!

http://www.skyview-wx.com/

 

Copyright 2009

Skyview Weather

Wettest Years in Denver History

With all of the wet weather recently and the precipitation surplus of 4.71” at DIA so far this year I thought it would be interesting to look at the top 10 wettest years in Denver history and see if we even have a chance at the top 10.  It is surprising that this topic even comes up as the year began very dry in January and February.  It was not until the last couple weeks of March when the weather pattern became more active and continues currently.  Here is a list of the 10 wettest years in Denver history.

1.      23.31” in 1967

2.      22.96” in 1909 and 1973

3.      21.87” in 1965

4.      21.58” in 1957

5.      21.52” in 1969

6.      21.43” in 1891

7.      21.42” in 1923

8.      20.95” in 1999

9.      20.36” in 1979

10.  20.32” in 1991

The most recent year to reach the top ten was in 1999 with 20.95” of precipitation.  So far this year as of July 31st DIA has reported 13.94” of precipitation.  To reach the top 10 DIA would need to record 6.38” of precipitation for the rest of the year.  How probable is this?  Well if we just have “normal” precipitation from August through December, 5.56” would be the total.  This would leave 2009 just 0.82” shy of the 10 place or at 19.50” for the full year.  Since normal to above normal precipitation is expected for the rest of this year let’s look at what 25% above normal precipitation till the end of the year would look like.  25% would add on an additional 1.39” to the 5.56” of “normal” which would result in an additional 6.95” of precipitation for the year.  If DIA receives 25% above normal precipitation for the year then that put the yearly total at 20.89” or in 9th place.  Anything above 25% of “normal” is approaching the unrealistic but cannot be completely ruled out.   

It appears that we have a legitimate shot at reaching the top ten wettest years in Denver history this year.  All that needs to play out is slightly above normal precipitation from now until year’s end.  Sounds easy enough, but the problem is that months get drier and drier from here on out and after August the threat for heavy thunderstorm rainfall really tapers off.  It will take heavy wet snowfall during the fall and early part of the winter to make this year stand out as one of the wettest in Denver history.       

Drought Update

With the widespread precipitation of the last several months, little areas of drought remain in Colorado.

The map below shows forecasted temperature deviances for August 2009. As can be seen, it is expected that much of Colorado to have  normal temperatures for the month of August 2009, with far southwestern Colorado expected to have above normal temperatures. 

The map below shows forecasted precipitation deviances for August 2009.  Most of Colorado is expected to have above normal precipitation for August 2009.

Little in the way of drought remains in Colorado, with no changes expected.

July Summary

Cooler and wetter than normal conditions this summer persisted through the month of July along the Front Range of Colorado.  The average high for the month came in 4 degrees below normal and the mean temperature for the month was 3.2 degrees below normal, the same as June.  More impressive is that the high for the month was only 93 degrees and there were only 7 days during the month with a temperature of 90 or more compared to 15 on average.  Precipitation once again came in well above normal with 3.56” reported at DIA compared to 2.16” on average.  This resulted in 1.40” above normal precipitation for the month and 4.71” above normal for the year.  There were 15 days with measureable precipitation and 19 days with thunderstorms reported at DIA, both were well above normal.  With all the rain and thunderstorm activity percent of possible sunshine was only 58% compared to 71% on average.  A big change from last year at this time as July of 2008 was ranked in the top 5 driest and warmest July’s on record. 

July Stats

TEMPERATURE (IN DEGREES F)

 

 

 

 

 

 

AVERAGE MAX

84.0

NORMAL

88.0

DEPARTURE

-4.0

AVERAGE MIN

56.5

NORMAL

58.7

DEPARTURE

-2.2

MONTHLY MEAN

70.2

NORMAL

73.4

DEPARTURE

-3.2

HIGHEST

93 on the 24th

LOWEST

49 on the 31st

 

 

 

 

 

 

DAYS WITH MAX 90 OR ABOVE

7

NORMAL

15

DAYS WITH MAX 32 OR BELOW

0

NORMAL

0

DAYS WITH MIN 32 OR BELOW

0

NORMAL

0

DAYS WITH MIN ZERO OR BELOW

0

NORMAL

0

 

 

 

 

 

 

TEMPERATURE RECORDS

 

Record low high of 64 degrees on the 28th

 

 

 

 

 

 

 

HEATING DEGREE DAYS

 

 

 

 

 

 

MONTHLY TOTAL

13

NORMAL

1

DEPARTURE

12

SEASONAL TOTAL

13

NORMAL

1

DEPARTURE

12

 

 

 

 

 

 

COOLING DEGREE DAYS

 

 

 

 

 

 

MONTHLY TOTAL

181

NORMAL

261

DEPARTURE

-80

YEARLY TOTAL

275

NORMAL

422

DEPARTURE

-147

 

 

 

 

 

 

PRECIPITATION (IN INCHES)

 

 

 

 

 

 

MONTHLY TOTAL

3.56

NORMAL

2.16

DEPARTURE

1.40

YEARLY TOTAL

13.94

NORMAL

9.23

DEPARTURE

4.71

GREATEST IN 24 HOURS

1.03” from the 20th into the 21st

DAYS WITH MEASURABLE PRECIPITATION

15

 

 

 

 

 

SNOWFALL (IN INCHES)

 

 

 

 

 

 

MONTHLY TOTAL

0

NORMAL

1.3

DEPARTURE

-1.3

SEASONAL TOTAL

38.1

NORMAL

61.7

DEPARTURE

-23.6

GREATEST IN 24 HOURS

NA

GREATEST DEPTH

NA

 

 

 

 

 

 

WIND (IN MILES PER HOUR)

 

 

 

 

 

 

AVERAGE SPEED

8.2 mph

PEAK WIND GUST

53 mph from the northwest

 

 

 

 

 

 

MISCELLANEOUS WEATHER

 

 

 

 

 

 

NUMBER OF DAYS WITH THUNDERSTORMS

19

NORMAL

11

NUMBER OF DAYS WITH HEAVY FOG

2

NORMAL

< 1

NUMBER OF DAYS WITH HAIL

1

 

 

PERCENT OF SUNSHINE

58%

NORMAL

71%

August Preview

Summer slowly begins to lose its grip during the month of August as days become noticeably shorter towards the end of the month.  The beginning of August can still be very hot though as the all time record high temperature for Denver of 105 was recorded during this month.  Severe weather becomes less common as the ground begins to cool and slow moving thunderstorms producing heavy rainfall become the greatest thunderstorm threat.  The average high temperature for August is 86 degrees with an average low of around 57.  This month the Front Range will likely experience cooler than normal temperatures once again this month.  Precipitation begins to fall off from previous months with around 1.82” on average.  This should not be a surprise to anyone, but above normal precipitation is likely for the month.  In fact we could be approaching a full years worth of precipitation by the end of the month!  With cooler and wetter conditions expected the percent of possible sunshine will also be lower than the 71% of average. 

 

DENVER'S NOVEMBER CLIMATOLOGICALLY NORMAL

(NORMAL PERIOD 1971-2000)

 

 

TEMPERATURE

 

 

 

AVERAGE HIGH

86.0

AVERAGE LOW

57.4

MONTHLY MEAN

71.7

DAYS WITH HIGH 90 OR ABOVE

9

DAYS WITH HIGH 32 OR BELOW

0

DAYS WITH LOW 32 OR BELOW

0

DAYS WITH LOWS ZERO OR BELOW

0

 

 

PRECIPITATION

 

 

 

MONTHLY MEAN

1.82"

DAYS WITH MEASURABLE PRECIPITATION

9

AVERAGE SNOWFALL IN INCHES

0

DAYS WITH 1.0 INCH OF SNOW OR MORE

0

 

 

MISCELLANEOUS AVERAGES

 

 

 

HEATING DEGREE DAYS

9

COOLING DEGREE DAYS

217

WIND SPEED (MPH)

8.0mph

WIND DIRECTION

South

DAYS WITH THUNDERSTORMS

8

DAYS WITH DENSE FOG

1

PERCENT OF SUNSHINE POSSIBLE

71%

 

 

EXTREMES

 

 

 

RECORD HIGH

105 on August 8, 1878

RECORD LOW

40 on 24-26 in 1919, 8/22/1904

WARMEST

76.8 degrees in 1937

COLDEST

66.5 degrees in 1915

WETTEST

5.85" in 1979

DRIEST

0.02" in 1924

SNOWIEST

0.0"

LEAST SNOWIEST

0.0"
 

Sunrise/Sunset (Jul - December Denver area)

              JUL                AUG                SEP            OCT               NOV            DEC
______________________________________________________________________________
            sr - ss            sr - ss             sr - ss          sr - ss             sr - ss           sr - ss
 01  0535-0831 | 0559-0813 | 0628-0732 | 0656-0643 | 0629-0457 | 0702-0436  01
 02  0536-0831 | 0600-0812 | 0629-0730 | 0657-0641 | 0630-0456 | 0703-0435  02
 03  0536-0831 | 0601-0811 | 0630-0729 | 0658-0640 | 0631-0455 | 0704-0435  03
 04  0537-0831 | 0601-0810 | 0630-0727 | 0659-0638 | 0632-0454 | 0705-0435  04

 05  0538-0831 | 0602-0809 | 0631-0725 | 0700-0637 | 0633-0453 | 0706-0435  05
 06  0538-0830 | 0603-0808 | 0632-0724 | 0701-0635 | 0634-0452 | 0706-0435  06
 07  0539-0830 | 0604-0807 | 0633-0722 | 0702-0634 | 0635-0451 | 0707-0435  07
 08  0539-0830 | 0605-0805 | 0634-0721 | 0703-0632 | 0637-0450 | 0708-0435  08

 09  0540-0830 | 0606-0804 | 0635-0719 | 0704-0630 | 0638-0449 | 0709-0435  09
 10  0541-0829 | 0607-0803 | 0636-0717 | 0705-0629 | 0639-0448 | 0710-0435  10
 11  0541-0829 | 0608-0802 | 0637-0716 | 0706-0627 | 0640-0447 | 0711-0435  11
 12  0542-0828 | 0609-0800 | 0638-0714 | 0707-0626 | 0641-0446 | 0711-0435  12

 13  0543-0828 | 0610-0759 | 0639-0712 | 0708-0624 | 0642-0445 | 0712-0436  13
 14  0544-0827 | 0611-0758 | 0640-0711 | 0709-0623 | 0643-0444 | 0713-0436  14
 15  0544-0827 | 0612-0757 | 0641-0709 | 0710-0621 | 0644-0444 | 0714-0436  15
 16  0545-0826 | 0613-0755 | 0642-0708 | 0711-0620 | 0646-0443 | 0714-0436  16

 17  0546-0826 | 0614-0754 | 0643-0706 | 0712-0618 | 0647-0442 | 0715-0437  17
 18  0547-0825 | 0615-0752 | 0644-0704 | 0713-0617 | 0648-0442 | 0715-0437  18
 19  0547-0824 | 0616-0751 | 0644-0703 | 0714-0615 | 0649-0441 | 0716-0438  19
 20  0548-0824 | 0616-0750 | 0645-0701 | 0715-0614 | 0650-0440 | 0717-0438  20

 21  0549-0823 | 0617-0748 | 0646-0659 | 0716-0613 | 0651-0440 | 0717-0439  21
 22  0550-0822 | 0618-0747 | 0647-0658 | 0717-0611 | 0652-0439 | 0718-0439  22
 23  0551-0821 | 0619-0745 | 0648-0656 | 0719-0610 | 0653-0439 | 0718-0440  23
 24  0552-0821 | 0620-0744 | 0649-0654 | 0720-0609 | 0654-0438 | 0718-0440  24

 25  0552-0820 | 0621-0742 | 0650-0653 | 0721-0607 | 0656-0438 | 0719-0441  25
 26  0553-0819 | 0622-0741 | 0651-0651 | 0722-0606 | 0657-0437 | 0719-0441  26
 27  0554-0818 | 0623-0739 | 0652-0650 | 0723-0605 | 0658-0437 | 0720-0442  27
 28  0555-0817 | 0624-0738 | 0653-0648 | 0724-0603 | 0659-0436 | 0720-0443  28

 29  0556-0816 | 0625-0736 | 0654-0646 | 0725-0602 | 0700-0436 | 0720-0444  29
 30  0557-0815 | 0626-0735 | 0655-0645 | 0726-0600 | 0701-0436 | 0720-0444  30
 31  0558-0814 | 0627-0733 |                      | 0727-0558 |                      | 0720-0445  31

 

 Rainfall

May 2009 to October 2009

City

May

June

July

Aug Sept

Seasonal Totals

Aurora (Central)

2.99 4.06 4.25     11.30
Brighton 2.13 4.02 3.07     9.22
Broomfield 1.38 1.69 1.34     4.41

Castle Rock 4 NE

2.20 2.09 2.87     4.29

Colorado Sprgs Airport

1.17 2.91 3.82     7.90
Denver DIA 1.30 4.86 3.56     9.72

Denver Downtown

3.15 3.07 2.56     8.78

Golden

2.68 3.15 2.62     8.45

Fort Collins

2.24 4.85 4.04     11.13

Highlands Ranch

3.23 2.28 3.07     8.58

Lakewood

3.90 3.90 3.07     10.87

Littleton

3.15 3.19 2.48     8.82

Parker

1.81 4.33 3.66     9.80

Sedalia - Hwy 67

2.40 3.54 4.09     10.03

Thornton

2.17 2.64 1.89     6.70

Westminster

2.77 3.92 2.55     9.24

Wheatridge

2.44 3.19 2.44     8.08