President Barack Obama’s acceptance of his party’s nomination for reelection Thursday has been moved indoors to Charlotte’s Time Warner Cable arena. Democratic National Convention organizers said the threat of severe weather was the reason for the move from the planned outdoor venue. Read the rest of this story on Examiner.com
Starting as a tropical wave off the coast of Africa on August 22nd, Hurricane Kirk never presented a threat to land as it stayed well out over the Atlantic. As the storm weakened and began to dissipate yesterday, the National Hurricane chose to use a famous line from Star Trek to describe the storm’s fate. Read the rest of this story on Examiner.com
Denver has seen a record-setting summer with extraordinarily warm temperatures and dry conditions. The question on everyone’s mind now is whether or not September will bring some relief.
Current indications are that overall the month will remain unseasonably warm and dry. However, temperatures will cool as is normal for September.
As temperatures start to drop, September usually reminds us that summer is at an end and fall is now here. Sunshine is predominant though as the month actually has the highest percentage of sun out of any month. Sunny days and clear, cool nights are the standard weather pattern for the month.
Get a complete look at September’s weather and more details as to what we can expect this year here.
Normally September is a relatively quiet month however we do occasionally see some extraordinary conditions. Our look back at this week in Denver weather history shows the earliest seasonal snowfall in Denver history, damaging lightning and the destruction of the Fourmile Canyon wildfire.
From the National Weather Service:
1-5
In 1995…record breaking heat occurred on the first 5 days of the month when the temperature climbed into the 90’s on each day. Record high temperatures of 97 degrees on both the 1st and 4th equaled the all-time record maximum for the month. High temperature of 95 degrees on the 3rd was a record for the date. High temperatures of 94 degrees on both the 2nd and the 5th were not records. The low temperature of 64 degrees on the 4th equaled the record high minimum for the date.
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In 1978…the temperature reached 90 degrees or more on seven consecutive days with the highest temperature…94 degrees… Recorded on both the 4th and 6th.
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In 1938…heavy cloudbursts in the foothills near the top of Genesee Mountain caused flash flooding on Bear Creek at Morrison. Nearly 8 inches of rain fell just north of Morrison in 6 hours and drowned 6 people in a car between Morrison and Kittredge. Damage was estimated at nearly a half million dollars. Flash flooding also occurred on south Boulder Creek in Eldorado Springs. Rainfall totaled 4.42 inches in Eldorado Springs…and rainfall was estimated to more than 6 inches in the foothills west of the town. Many buildings and residences were damaged in Eldorado Springs…and bridges were swept away. The high waters forced residents from their homes as far downstream as Erie. This was the flood of record on South Boulder Creek.
In 1973…hail to 3/4 inch diameter was reported in Boulder.
In 1987…lightning struck two men who were standing under a tree in downtown Denver. Both were seriously injured and hospitalized.
In 1996…lightning sparked a brush fire in the south buffer zone of the Rocky Flats Environmental Test Facility. No structures were damaged…but the fire burned about 100 acres of grassland before being contained.
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In 1892…there was a trace of rainfall each day. This… Together with a trace of rain on both the 7th and 8th…was the only rainfall of the month…making the month the driest on record. The monthly record was equaled in 1944.
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In 1901…a thunderstorm produced rain…hail of unknown size… And south winds sustained to 40 mph with gusts to 43 mph.
In 1961…Labor Day snow storm is the earliest date of the first snow…trace and measurable…of the season. The heavy wet snow broke many limbs from trees that were still in full foliage. The storm produced 4.2 inches of snowfall at Stapleton Airport with nearly a foot of snow in western suburbs and in the foothills. Minimum temperature of 33 degrees was a record for the date and the coldest ever recorded so early in the season.
In 1999…severe thunderstorms dumped large hail across metro Denver. Hail as large as 1 inch in diameter was measured near Cherry Creek in Aurora and near Bennett. Hail to 3/4 inch in diameter fell in the city of Denver.
In 2002…a thunderstorm produced a wind gust to 51 mph at Denver International Airport.
In 2003…very heavy thunderstorm rain washed out parts of the Virginia Canyon Road above Idaho Springs. Up to 4 feet of mud reportedly washed down the road during the storm. Several vehicles were trapped on the road. In Idaho Springs…several streets…including the main street… Were also buried in mud and gravel. Some buildings in town experienced minor flooding…including the basement of the town library and the police station.
Continue reading September 2 to September 8 – This Week in Denver Weather History
There would be no break from the hot and dry summer of 2012 in August as records continued to tumble and the ground remained parched. While a few cold fronts provided some relief, they were short-lived and high pressure dominated during the month.
Denver recorded an average temperature of 75.0 degrees which was 2.5 degrees above normal. This ties August 1994 as the 5th warmest August since record keeping began in 1872.
In all, 20 days recorded high temperatures at or above 90 degrees at Denver International Airport. By the end of the month 2012 moved into the record books as having the most seasonal 90 degree days of any year (66 as of 8/31). Highs ranged from 98 degrees on the 3rd, 6th, 9th, and 27th to a low of 47 degrees on the 17th.
Here in Thornton our average temperature was quite a bit cooler, although still above average in comparison to recent years. Thornton’s average for the month came in at 72.7 degrees.
Thornton recorded 17 days of 90 degree or hotter high temperatures. Our hottest temperature was 96 degrees which occurred on the 27th and 29th. The coldest temperature recorded was 48 degrees on the 17th and 19th.
Precipitation continued to elude the Mile High City as a mere 0.11 inch fell into the rain bucket during the month, and that all came in a single day. This was far below the normal of 1.68 inches for August and put 2012 into the books as the 4th driest August on record.
Thornton fared only slightly better on the precipitation front as we recorded 0.31 inch of rain. As with Denver, that total came all in a single day, the 1st of the month.
More on ThorntonWeather.com:
August 2012 Graphs
Denver’s Official August 2012 Climate Summary
...THE DENVER CO CLIMATE SUMMARY FOR THE MONTH OF AUGUST 2012...
CLIMATE NORMAL PERIOD 1981 TO 2010
CLIMATE RECORD PERIOD 1872 TO 2012
WEATHER OBSERVED NORMAL DEPART LAST YEAR`S
VALUE DATE(S) VALUE FROM VALUE DATE(S)
NORMAL
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TEMPERATURE (F)
RECORD
HIGH 105 08/08/1878
LOW 40 08/26/1910
08/25/1910
08/24/1910
HIGHEST 98 08/27 87 11 99 08/25
08/03
08/06
08/09
LOWEST 47 08/17 40 7 55 08/20
AVG. MAXIMUM 91.0 87.2 3.8 92.7
AVG. MINIMUM 58.9 57.9 1.0 61.3
MEAN 75.0 72.5 2.5 77.0
DAYS MAX >= 90 20 11.5 8.5 22
DAYS MAX = .01 1 8.6 -7.6 3
DAYS >= .10 1 4.3 -3.3 1
DAYS >= .50 0 1.2 -1.2 0
DAYS >= 1.00 0 0.3 -0.3 0
GREATEST
24 HR. TOTAL 0.11 08/11 TO 08/11 08/03 TO 08/03
SNOWFALL (INCHES)
RECORDS
TOTAL 0.0 NO SNOW EVER RECORDED IN AUGUST
TOTALS 0.0 NO SNOW EVER RECORDED IN AUGUST
DEGREE_DAYS
HEATING TOTAL 0 10 -10 0
SINCE 7/1 0 16 -16 0
COOLING TOTAL 319 244 75 382
SINCE 1/1 1122 688 434 863
FREEZE DATES
RECORD
EARLIEST 09/08/1962
LATEST 06/08/2007
EARLIEST 10/07
LATEST 05/05
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WIND (MPH)
AVERAGE WIND SPEED 9.9
RESULTANT WIND SPEED/DIRECTION 3/217
HIGHEST WIND SPEED/DIRECTION 38/330 DATE 08/30
HIGHEST GUST SPEED/DIRECTION 45/330 DATE 08/30
SKY COVER
POSSIBLE SUNSHINE (PERCENT) MM
AVERAGE SKY COVER 0.50
NUMBER OF DAYS FAIR 8
NUMBER OF DAYS PC 22
NUMBER OF DAYS CLOUDY 1
AVERAGE RH (PERCENT) 34
WEATHER CONDITIONS. NUMBER OF DAYS WITH
THUNDERSTORM 4 MIXED PRECIP 0
HEAVY RAIN 0 RAIN 0
LIGHT RAIN 9 FREEZING RAIN 0
LT FREEZING RAIN 0 HAIL 0
HEAVY SNOW 0 SNOW 0
LIGHT SNOW 0 SLEET 0
FOG 0 FOG W/VIS
The National Weather Service has begun a significant upgrade to Denver’s weather radar. The new dual-polarization (dual-pol) radar brings 14 new data types and will greatly enhance the ability of forecasters to monitor and analyze storms.
During the upgrade while Denver’s radar is inoperative, ThorntonWeather.com’s radar page will be using the adjacent radar in Cheyenne. This will somewhat limit the ability to monitor storms during the two week period while the work is taking place.
The information below is from the National Weather Service and describes the dual-pol upgrade and what it brings to the table in terms of enhancements with monitoring severe weather.
From the National Weather Service:
| During a two-week period, beginning August 30, 2012, the Doppler radar at your National Weather Service Forecast Office will undergo an upgrade to incorporate new technology. For these two weeks, radar data will be unavailable from NWS Denver/Boulder!
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| Current NWS Doppler radars transmit and receive pulses of radio waves in a horizontal orientation. As a result, the radar only measures the horizontal dimensions of targets (e.g. cloud and precipitation droplets). Dual-polarimetric radar transmits and receives pulses in both a horizontal and vertical orientation. Therefore, the radar measures both the horizontal and vertical dimensions of targets. Since the radar receives energy from horizontal and vertical pulses, we can obtain better estimates of the size, shape, and variety of targets. It is expected that this will result in significant improvements in the estimation of precipitation rates, the ability to discriminate between precipitation types (e.g. hail vs. rain), and the identification of non-meteorological returns, such as chaff, ground clutter, and smoke plumes from wildfires that are not uncommonly detected by weather radar systems such as WSR-88D. | |
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The full benefit of dual-pol radar, however, will not be fully realized until NWS forecasters and research meteorologists develop real-time expertise. |
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| A radio wave is a set of oscillating electric and magnetic fields, oriented 90 degrees to each other. Polarization of the wave is the direction, or orientation, of the electric field.
Horizontal Polarization |
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The electric field is oriented horizontally, along the x-axis (blue). The magnetic field is oriented vertically along the y-axis (white). |
| Vertical Polarization | |
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The electric field is oriented vertically, along the y-axis (orange). The magnetic field is oriented horizontally along the x-axis (white). |
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An extremely powerful magnitude 7.6 earthquake has occurred east of the Philippines and has the potential to generate a tsunami across the Pacific. Tsunami warnings and watches have been issued for parts of the Pacific Rim. Read the rest of this story on Examiner.com
Hyperbole from climate change alarmists is nothing new with many of the biggest purveyors of the theory seemingly wanting to one-up the comments of the others. Former vice president Al Gore has always been one to provide interesting quotes and this week equated extreme weather events to Biblical catastrophes. Read the rest of this story on Examiner.com including video of Gore’s commentary.
On the surface of the Earth hurricanes bring destruction and oftentimes death with a ferocity unlike any other type of weather. Viewed from above however hurricanes seem almost tranquil and in some ways beautiful as is seen in new video of Hurricane Isaac from the International Space Station. Check out the stunning video as well as amazing photos of previous hurricanes as seen from space.
We now have the fourth hurricane of the 2012 Atlantic season as Isaac has strengthened prior to making landfall tonight. The National Hurricane Center says that Hurricane Isaac is packing Category 1 strength winds of 75mph. Landfall is expected tonight on the eve of the 7th anniversary of Hurricane Katrina. Read the rest of this story on Examiner.com including the storm’s forecast track, satellite imagery and more.
Check out this impressive two-day time lapse video showing two days of Isaac’s evolution and track from tropical storm to hurricane.
