THE YEAR 2011
JANUARY 2011 SUMMARY
January was colder than average as the monthly mean temperature was 34.8 F, a -1.3 F departure,
and it was drier than average (when compared to Ashland, VA records).
The first two days in January were the warmest two days of the month.
There were 28 days where the minimum temperature dropped below freezing
and two days that the maximum temperature stayed below freezing.
The 2.22 inches of precipitation for January was a -1.14 inch departure when compared to the Ashland,
VA average, however, 2009 had less with only 1.95 inches.
The maximum precipitation recorded in a day was 1.27 inches on January 26th
and is the most ever recorded in a calendar day at the Glen Allen station for the month January.
The month had 11 days with precipitation which is also a new record for January.
The mean temperature for Glen Allen was 34.8 F which made January the coldest since 2009.
The maximum temperature for January was 60 F on January 1st but was the lowest maximum
monthly temperature ever recorded at this station for January.
January also had the lowest average maximum temperature which was caused in part by the cloudy month.
Glen Allen also had the lowest average temperature range ever recorded for the month of January.
The average temperature range at the Airport was the lowest since 2004.
The lowest minimum was 13 F which was recorded here on the 23rd.
The lowest barometric pressure of the month was 29.37 inches and recorded on the 8th ;
the highest was only 30.47 inches on January 4th.
This was the first January that thunder was recorded at the Glen Allen station.
The maximum wind gust for the month was only 26 mph that occurred on the 29th of the month
from the SSW at 1503 but the windiest day occurred on January 15 with a 104.5 mile wind run.
This month was the cloudiest of the past three years and in part explains the
lowest average temperature range for January at the Glen Allen station.
The Richmond International Airport set one record for the month.
The 1.38 inches of precipitation that fell on the 26th was the most precipitation ever recorded for the date.
The previous record was 1.28 inches in 1966. January had the 28th lowest mean temperature of the last 114 years.
January was the 40th driest of the past 114 years.
Only 2 inches of snow fell at the Richmond International Airport this past January
making it the 56th least amount of snowfall in the last 114 years.
FEBRUARY 2011 SUMMARY
February was much warmer than average as the monthly mean temperature was 44.8 F, a +5.7 F departure,
and the warmest February at the Glen Allen Station and was much drier than average (when compared to Ashland, Virginia records).
There were 16 days the minimum temperature dropped below freezing and 0 days that the maximum didnít climb above freezing.
The 1.53 inches of rain for February was a -1.47 inch departure when compared to the Ashland, VA average.
The maximum rainfall recorded in a day was only 0.64 inches on the 28th.
Measurable precipitation occurred on only eight days and it is noteworthy that there
was only 0.01 inches of precipitation from and including the 6th to the 21st a sixteen day period.
The total frozen precipitation was 0.1 inches for the month recorded on the 10h which
was a negative 4.9 inch departure compared to Ashland, Virginia records.
The maximum temperature for February was 77 F on the 18th and the Richmond International Airport
also had 77 F which tied the record daily maximum temperature set in 1976.
This is the highest February temperature on record for Glen Allen.
The lowest minimum this month was 20 F recorded on the 9th and 11th.
There were four days (14th, 17th 18th, 28th) that the temperature was 70 degrees F or higher.
The lowest dew point temperature was 3.0 F on the 19th at 1059.
Also on the 19th the relative humidity was only 10 percent the lowest reading on my records.
This same day the maximum wind gust was 40 mph from the north that occurred at 1424 hours
making this a near record high fire index for the area.
This was also the windiest month on record at this station. The total wind run was 2092.9 miles.
The highest wind run for a day was 156.4 miles on February 25 which was the highest since
November 12, 2009 when a reading of 162.5 miles was recorded.
The highest barometer recorded for the month was 30.43 inches on the 3rd and the lowest was 29.42 inches on the 25th.
WINTER RECORDS-- DECEMBER, JANUARY, FEBRUARY---
Winter Mean Ashland Dep. Precip. Ashland Dep. Snow Ashland Dep.
Temp. Average F Inches Average Inches Inches Average Inches
Dec 32.68 38.97 -6.29 3.02 3.30 -0.28 7.6 2.0 5.6
Jan 34.84 36.12 -1.28 2.22 3.36 -1.14 1.5 5.8 -4.3
Feb 44.82 39.15 5.67 1.53 3.00 -1.47 0.1 5.0 -4.9
SUM 112.34 114.24 -1.90 6.77 9.66 -2.89 9.2 12.8 -3.6
Ave. 37.45 38.08 -0.63 2.26 3.22 -0.96 3.1 4.3 -1.2
MARCH 2011 SUMMARY
March was warmer than average as the monthly mean temperature was 48.1 F, a + 1.3 F departure,
and was also wetter than average (when compared to Ashland, Virginia records).
The 4.24 inches of rain for March was a + 0.49 inch departure when compared to the Ashland,
The maximum rainfall recorded in a day was 1.40 inches on the 10th.
The total snowfall was only 0.2 inches for the month recorded on the 27th
which was a -1.5 inch departure compared to Ashland records.
Mid-March this year was warmer than average and the end was much colder giving a near average
result and less snowfall than average and also the least in the past 3 years.
The most unusual event in March was the hail near sunrise on the 21st.
A thunderstorm passed the Glen Allen station around 0710 to 0720 AM giving about two minutes of hail
from 0712 to 0714 A.M. (+/- 3 mins.) and gave only 0.04 inches of rain and 0.07 inches with the melted hail.
The smallest hail was 0.25 inches and the largest was 0.5 inches but most averaged about 3/8 inch.
It was interesting to have hail with almost most no wind or rain and the precipitation starting as hail
and rain and also occurring around sunrise.
The hailstone consistency was white ice but some hail had a band or layer of clear ice running through it
and were irregular shaped and spheres.
Richmond International Airportís March mean temperature of 48.7 F was the 50th warmest of the past
115 years and the precipitation of 4.28 inches was the 32nd wettest in the past 115 years.
The Airport had two records: 84 F on the 18th ; the old record was 83 F in 1927 and the 5 F
low temperature range tied the old record set in 1985 and 1961.
There were 9 days the minimum temperature dropped below freezing. The maximum temperature
for March was 82 F on the 18th at this station.
The lowest minimum was 28 F recorded at this station on the 4th, 8th, 28th, 29th.
A very low relative humidity of 14% was recorded here on the 11th.
The maximum wind gust of 37 mph from the NNE occurred on the 6th at 1955 hours.
March was also the third windiest month at this station with a total wind run of 1825 miles.
The highest barometer recorded for the month was 30.63 inches on the 3rd and 4th.
This was the highest this station has recorded in March and the highest barometric pressure
since December 12, 2009 when the pressure was also 30.63 inches of mercury.
The lowest barometric pressure was 29.37 inches on the 23rd.
APRIL 2011 SUMMARY
April was much warmer than average as the monthly mean temperature was 61.4 F,
a +4.8 F mean temperature departure, and was drier than average when compared to Ashland, Virginia records.
This was only 0.1 F cooler than the warm April of last year.
The 2.41 inches of rain for April was a -0.66 inch departure when compared to the Ashland,
VA average and 10.40 inches for the year.
Last year at this time we had 15.74 inches of rain for the year.
The maximum rainfall recorded in a day was 1.08 inches on the 16th.
Measurable precipitation occurred on 13 days and nine of these days had less than 0.07 inches.
April was a very windy month with a total wind run for the month of 2,773.2 miles the windiest on record for April.
The windiest day was the 4th with a wind run of 226.1 miles a new daily record for this station.
The maximum temperature for April was 88 F on the 24th and there were five days that the temperature was 85 F or higher.
The Richmond International Airport had 87 F the highest maximum temperature for the date on the 4th;
the previous record was 86 F in 1956.
The Airport tied the highest minimum temperature for the date with a temperature of 67 F on the 26th.
The lowest minimum was 32 F recorded on the 6th and there were two days with light scattered frost.
The maximum wind gust was 39 mph from SSW that occurred on the 5th at 0023.
The highest barometer recorded for the month was 30.37 inches on the 22nd.
The lowest barometric pressure was 29.29 inches on the 5th, the lowest since December 13th when it was 29.25 inches.
May was warmer than average but 1.0 F cooler than May last year as
the monthly mean temperature was 68.6 F.
This is a +4.0 F departure, and was also above average in precipitation
(when compared to Ashland, Virginia records).
The 5.16 inches of precipitation for May was a +1.31 inch departure
when compared to the Ashland, VA average.
May had three days with more than 1 inch of rain and 12 days with measurable rainfall.
The maximum precipitation recorded in a day was 1.58 inches on the 17th
and thunder was heard on nine days during May.
We had 3.40 inches of rain in five consecutive days from the 13th to the 17th.
On the 13th, there was a lightning strike while drizzle was falling.
The maximum temperature for May was 94 F on the 30th and 31st.
There were 8 days that the maximum temperature was 85 F or above.
The highest minimum temperature recorded here for the month was 73 F on May 26th.
The Richmond International Airport had 5 ties / records
Record High Minimums: May 26th 70 F tied the old record set in 2006
Record High Maximums: May 31st 98 F tied the old record in 1991
May 30th 70 F tied the old record set in 1959
Record daily mean temperatures: May 26th 81.5 F new record; the old record was 81.0 F in 1984
Daily Precipitation: May14th 1.74 inches the old record was 1.48 inches in 1972.
The Airport mean temperature was the 16th warmest in 115 years.
The Airport rainfall was 4.35 inches the 40th wettest in 115 years.
The maximum wind gust at Glen Allen was 36 mph from the north that occurred on the 4th at 0517.
May 2011 had more wind and was sunnier than May last year.
The Spring Season was much warmer than average and a little drier than average
when compared to Ashland, VA records.
As seen in the chart below, spring was warmer and wetter than average.
SPRING RECORDS-- MARCH, APRIL, MAY---
Ashland Allen Temp. Ashland Allen Precip.
Mean Mean Depart. Precip. Total Depart.
Temp. Degrees F Average Precip Inches
Mar. 46.74 48.05 1.31 3.75 4.24 0.49
Apr. 56.61 61.40 4.79 3.07 2.41 -0.66
May 64.56 68.55 3.99 3.85 5.16 1.31
SUM 167.91 178 10.09 10.67 11.81 1.14
Spring 55.97 59.33 3.40 3.56 3.94 0.38
June was hotter than average by 4.6 F and 3.2 F less than June last year as the monthly mean temperature was 76.9 F,
and was below average in precipitation (when compared to Ashland, Virginia records).
The 2.70 inches of precipitation for June was a -0.78 inch departure when compared to the Ashland, VA average.
There were 12 days in June with maximum temperatures of 90 F.
The maximum precipitation recorded in a day was 1.10 inches on the 28th when 0.33 inches fell in five minutes which was
the most intense precipitation since July 29, 2010 when 0.35 inches fell in 5 minutes.
Thunder was heard on eight days during June but none of the storms were severe. The maximum temperature for June was 98 F on the 9th.
The Richmond International Airport also had 98 F on the 9th tying the record for the date.
They also tied the record high minimum temperature of 74 F on the 22nd.
The highest minimum temperature recorded here for the month was 75 F on June 23rd.
The Richmond International Airport reported the mean temperature for June of 78.0 F which tied for the 8th warmest since records
started in 1880 as both 1880 and 1994 also had a mean temperature of 78.0 F.
In the precipitation records from 1887 to 2011 the 3.03 inches was the 48th most rain in the past 125 years.
Glen Allen also had 10 days that the minimum temperature was 70 F or higher.
The lowest dew point temperature for June was 41.3 F on the 3rd at 1229 and the highest dew point was 77.0 F on the 1st at 1539.
The maximum wind for June came from the NNE on June 13 at 0739.
June was a little clearer and windier than average and the average relative humidity was about normal.
July was extremely hot again this year.
The Richmond International Airport had a mean monthly average of 82.1 F which was only 0.7 F less than last year
which was the hottest July since temperature records were started in 1880.
The July mean average temperature here was 81.5 F a +5.1 F departure when compared to Ashlandís average.
Julyís mean was only 0.5 F less this year when compared to last July.
The 3.69 inches of rainfall for July at Glen Allen was a -0.66 inch departure when compared to Ashlandís average.
The Richmond International Airport had 3.63 inches and was the 47th driest from 1887 to 2011.
July had 9 days with measurable rain with 1.71 inches or 46% of the monthís rainfall occurring on the 8th.
The Richmond International Airport had 1.72 inches on the 8th which is now a new daily record amount there.
At Glen Allen July had 22 days with 90 F or above temperatures the same as last year.
The maximum temperature for July was 102 F recorded on July 22nd which is the second highest maximum
temperature ever recorded here.
But with the high relative humidity the heat index hit 117.6 F at 1358; this was higher than any reading last year.
The Airport had 103 F on the 29th which set a daily maximum temperature record for the date.
They also set three daily high minimum temperature records on the 12th, 22nd, and 30th.
The minimum temperature on the 12th was 81 F which makes it the warmest night ever recorded for Richmond, Virginia.
On 20 nights the minimum temperature was 70 F or higher at the Airport.
A wind gust of 35 mph on the 3rd is thought to be the strongest wind gust recorded for July that occurred in a thunderstorm
in which lightning hit within 50 feet of my weather station and destroyed the anemometer.
The other equipment damaged was a Davis transmitter module #6152 which included the sun, rain, wind, temperature and relative humidity.
The wireless leaf and soil moisture/temperature transmitter #6345 and both leaf wetness sensors, solar radiation sensor,
temperature/relative humidity sensor, intercom system were destroyed. It also damaged two thermometers that monitored
soil temperature and leaf wetness sensor temperature. I have attached an image of the tree that was hit.
As of July 30th the Glen Allen Weather Station is back to full operation.
August was warmer than average as the monthly mean temperature was 78.5 F, a +1.0 F
mean temperature departure based on the new normals, and was wetter than average when compared to Ashland, Virginia records.
The 6.65 inches of rain for August was a +1.52 inch departure when compared to the Ashland, VA
average and the wettest month since December 2009.
It was very dry before the rain of the 14th with only 0.64 inches of rain occurring between
July 9th and August 12 a period of more than a month.
But with Irene it was also the wettest August in the past four years.
The maximum rainfall recorded in a day was 3.75 inches on the 27th which was 56 percent of the
monthís rainfall and measurable precipitation occurred on nine days.
The maximum temperature for August was 97 F on the 7th.
On thirteen days the maximum temperature was greater than or equal to 90 F.
The lowest minimum was 57 F recorded on the 23rd.
The maximum wind gust was 52 mph from the north that occurred on the 27th at 1753 hrs.
(Also a new record for Glen Allen, VA)
The Richmond International Airport had a gust to 71 mph during Hurricane Irene.
Irene set a maximum precipitation record for West Henrico Co. Ė Glen Allen Virginia for a 24 hour period of
3.85 inches and 3.75 inches in a calendar day.
Irene set a new wind run record of 284.1 miles on the 27th. (Glen Allen Station records since August of 2008)
Irene also gave the lowest barometer since April 26, 2010 of 29.20 inches on the 27th.
We also experienced a 5.8 magnitude earthquake on the 23rd at 1351 that was the strongest in 114 years.
On May 5, 1897 Giles Co. was estimated to have had an earthquake of 5.8 magnitude.
We were also awakened on the 25th at 0107 by a 4.5 magnitude quake as it rattled the metal pulls on the chest of drawers.
The Richmond International Airport had 7.10 inches of rain for August the 25th wettest August in the past 125 years.
It was also the largest daily rain since August 30, 2004 when 6.68 inches was recorded.
The Airport had an August mean temperature of 79.0 F which was the 16th hottest August in the past 125 years.
They set only two records for the date. On Aug. 1st 99 F tied for the highest maximum temperature and
the 5.36 inches of rain on the 27th set a new record of rainfall for the date.
SUMMER RECORDS-- JUNE, JULY, AUGUST---
NEW Glen NEW Glen
Ashland Allen Temp. Ashland Allen Precip.
Mean Mean Depart. Precip. Total Depart.
Temp. Degrees F Average Precip Inches
June 74.9 76.9 2.0 3.48 2.70 0.49
July 79.0 81.5 2.5 4.00 3.69 -0.66
Aug. 77.5 79.4 1.9 5.13 6.65 1.31
SUM 231.4 237.86 6.46 12.61 13.04 1.14
AVE. 77.13 79.29 2.15 4.20 4.35 0.38
The summer season was 2.2 F warmer when compared to Ashlandís averages and the rainfall was +0.38 inches above the average.
September was warmer and much wetter than average as the monthly mean temperature was 72.2 F,
a 0.4 F departure based on my three year average and a +1.9 F departure when compared to Ashland, Virginia
(new thirty year average).
The maximum temperature for September was 89 F on the 4th and 14th; the lowest minimum was 47 F recorded on the 16th.
The Richmond International Airport mean temperature was 72.5 which was the 25th warmest September since 1897.
But on the 17th the Airport had a high of only 61 F which was a new record low maximum temperature for the date
and a daily range of only 4 F which tied the record for the lowest daily temperature range.
The two previous records were 62 F in 1924 and a 4 F daily temperature range in 1957 and 1938.
The main event of the month occurred from the 6th to the 8th.
The remnants of Lee gave record rainfall amounts and many places received more rain than Glen Allen.
The 6.51 inches of precipitation for September at Glen Allen was a departure of +2.58 inch departure when compared to the Ashland,
VA average and a new record rainfall amount for September.
It was also the wettest month since December of 2009 at Glen Allen.
The maximum precipitation recorded in a day here was 2.27 inches on the 7th.
September had measurable precipitation on twelve days but 17 days when counting trace amounts
and was the second cloudiest month on record at Glen Allen.
The cloudiness caused the daily temperature to be the lowest on record for the month.
The cloudiness contributed to the highest average relative humidity and highest minimum temperatures on record for this station.
(Records since August of 2008)
The Richmond International Airport had 3.76 inches on the 7th a new record rainfall amount for the date
(previous record was 2.15 in 1934) and 8.95 inches for the month which is the 9th greatest rainfall total for September since 1887.
September was cloudier than average and the average relative humidity was 77.2% which was 13.7 % more than last September.
After the only cool period just after mid-September, that lasted four days,
Glen Allen had an exceptionally cloudy showery and muggy weather pattern that lasted until the end of the month.
There were two main events in October both of which had little effect on the West Henrico Co. Ė Glen Allen area.
The thunderstorms on October 13th produced three tornadoes in Quantico in Prince William County, in Boswell Tavern in Louisa County,
and the Lakewood area in New Kent County, VA.
The storm gave this station only 0.46 inches of rain and one very close lightning strike.
On the 29th a strong storm system moving up the East Coast (affecting ten states) dumped more than two feet of snow in NH
and left more than 3 million homes and businesses without power and caused at least twenty deaths.
October was cooler and drier than average at the Glen Allen Station when compared to the Ashland Station.
The monthly mean temperature was 58.6 F, a -0.8 F departure when compared to the Ashland, VA average.
The 3.32 inches of precipitation for October at Glen Allen was a -0.15 inch departure when compared to the Ashland, VA average.
The maximum temperature for October was 81 F and the lowest minimum temperature was 29 F recorded on October 30.
The cold was really felt as it was near 80 F on the 25th.
There were two frosts in October and both were heavy and killing on the 30th and 31st.
The Richmond data base recorded three records this month.
The low maximum temperature of 45 F recorded on the 29th as a record low maximum for the date; previous record was 46 F in 1925.
On October 12th the minimum temperature tied the previous record of 65 F set in 1983.
The maximum on the 12th was 68 F giving a daily temperature range of 3 the lowest range ever recorded on that date.
The previous record was 8 F set in 1985 and 1942.
It was the 58th warmest and the 59th wettest October in the Richmond records.
The highest dew point temperature for October was 72 F on the 13th at 1430 that made it feel like a summer's day.
The lowest dew point was 26.1 F on the 30th at 1536.
The maximum wind gust was 34 mph from the SSW that occurred on the 20th at 1057 preceding a cold front.
November was warmest on record (records since 2008) as the monthly mean temperature was 53.23 F,
a +4.2 F mean temperature departure when compared with Glen Allenís three year average.
November precipitation was 3.50 inches or a little drier than average when compared to Ashland, Virginia records.
November had a -0.15 inch departure when compared to Ashland, Virginia.
Measurable precipitation occurred on only seven days and was the second clearest November on record.
The clear weather of November gave the highest daily average temperature range in the past four years of 23.9 F.
The maximum temperature for November was 76 F on the 14th.
The lowest minimum was 26 F recorded on the 18th and there were five days with less than or equal to 32 F
but the first killing frost came on October 30th this year.
The lowest dew point temperature was on the 18th at 15.9 F. The maximum wind gust was 35 mph
from the SSW that occurred on the 27th at 1231 hrs.
The highest barometer recorded for the month was 30.52 inches on the 6th and 18th.
Richmond had 4.18 inches of rain the 28th wettest November of the past 114 years and the 2.47 inches on the 16th
was the 8th largest daily precipitation since 1887 for November.
The Airport had a mean temperature of 53.5 F which was the 8th warmest November of the past 114 years.
No daily records were set for Richmond during November.
FALL SEASON RECORDS-- SEPTEMBER, OCTOBER, NOVEMBER---
FALL Ashland Glen Allen Ashland Glen Allen
Season Mean Mean Temp. Precip. Total Precip.
Temperature Temp. Depart. F Average Precip Depart.
Sep. 70.3 72.2 1.9 3.93 6.51 2.58
Oct. 59.4 58.6 -0.8 3.47 3.32 -0.15
Nov. 49.9 53.2 3.3 3.65 3.50 -0.15
SUM 179.6 184.1 4.4 11.05 13.33 2.28
AVE. 59.9 61.4 1.5 3.68 4.44 0.76
The fall season was 1.5 F warmer when compared to Ashlandís averages and the rainfall was +0.76 inches above the average.
- DECEMBER 2011 SUMMARY
December was a very warm month as the monthly mean temperature was 46.0 F, a +6.1 F departure from average,
and was drier than average when compared to my Glen Allen records.
The average temperature this December was 13.3 F warmer than last December which was very cold.
December didnít set any daily records for warmth but was constantly warm.
Glen Allen had 6 days of >= 65 F and 12 days of >=60 F.
The lowest temperature was 25 F which was 9 F above the record highest minimum temperature for December at this station.
The lowest barometric pressure of the month was 29.44 inches recorded on the 7th and 27th;
the highest was 30.69 inches on December 11th.
The mean temperature for the Richmond International Airport was 46.3 F which made December the
6th warmest in the past 114 years and the 8th warmest in the past 132 years.
(The separation in records was done as the mean temperatures from 1880 to 1896 arenít very accurate.)
The two years in the above period that were warmer were 1891 and 1889.
The mean temperature used for 1891 for Richmond was 1.8 F warmer than the mean for Norfolk for the same period.
The mean for Richmond in 1889 was only 0.3 F less than Norfolk when comparing the mean temperatures between 1897 and 2010.
On average Norfolk runs 3.7 F warmer for December than Richmond.
Richmondís December minimum temperature was 25 F that ties 1994 for the highest monthly minimum temperature in the past 114 years.
Also Richmondís lowest daily mean temperature was 36.5 F which was the highest recorded in the past 114 years for December.
December didnít even have a trace of snow and this has happened only 12 times
in the past 113 years; the average snowfall for December is 2.1 inches.
The 2.03 inches of precipitation for December was -1.23 inch departure and the 27th driest December of the past 114 years.
The only stormy weather came on the 7th in a thunderstorm associated with a cold front that gave Glen Allen winds to 33 mph.
Just 3.6 miles southwest of this station winds moved a heavy propane gas grill across a deck, estimated winds of 50 to 60 mph,
and winds of 64 mph were reported at Richmond International Airport.