Relative Humidity and Dewpoint

Tuesday, October 2, 2017 provided an excellent example of why meteorologists turn to dewpoint temperature to get a better picture of moisture in the air. Relative humidity is a good index to monitor drying potential, disease potential, or fire risk, but relative humidity is relative to the air temperature. When the air temperature changes, the relative humidity changes. Dewpoint temperature is an absolute measure of water vapor, independent of air temperature.

Wheat dew on heads(2)

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Inversion, Dispersion and Spraying

You’ve got a busy day ahead! If part of the day’s work is spraying, it’s tempting to kick on the sprayer as the morning sun lights up your crop and soil. If you’re spraying a herbicide, you don’t want to spray when an inversion is present.

Morning mist is a visible indicator of an inversion, but don’t assume an inversion is gone. The mist maybe gone, but  inversion may still be in place. Read on for a sure way to know when an inversion has fully dissipated.

morning-mist-wallpaper-c2017-08-08.AgBlog.Inversion Dispersion.Morning Mist Soybean Continue reading

Beaver 2017, Too Long Between Rains

Western Oklahoma’s latest rain was critical to the success of this year’s winter wheat and canola crops. It also brought much needed relief to fire fighters as it drenched areas where large, devastating fires occurred in early March. The rain came with storms on March 28-29, 2017.

rainrfc.48hr

If we just looked at rainfall totals, we’d be hard pressed to believe that 2017 is dealing with “dry” year conditions. That’s because rainfall totals since January 1st fail to tell the story of real-world conditions. One has to drill down and scrutinize rainfall totals under the microscope of daily rainfall events and amounts. And the Oklahoma Mesonet has just the tool to do that, the Mesonet Long-Term Averages Graph maker.  Continue reading

Wind’s Weather Role in NW Oklahoma Complex Fires (part 3 of 3)

The stage was set. The players for a drama of tragic proportions assembled. Two leads waited their cue. Already on stage were fine dead fuels from previous growing seasons, low moisture in February, and super low humidities. The next player in the drama entered, high wind speeds. This article is part 3 of 3 articles exploring weather conditions that set the stage for the Northwest Oklahoma Complex Fires that broke out on Monday, March 6, 2017.

2017-03-16.1Mb.Fire wall behind field and farmer.Terena Burke Bridwell.Barby Ranch.The Oklahoman

(Photo: Terena Burke Bridwell/Barby Ranch Beaver County)

At 11:00 AM March 6th winds across Beaver County were out of the southwest. Wind speed at the Oklahoma Mesonet Beaver site was 37 miles per hour. Continue reading

Relative Humidity’s Weather Role in NW Oklahoma Complex Fires (part 2 of 3)

As relative humidities drop, standing, dead plant stems dry out. Dense, dead, dry grasses were the primary fuel source for the devastating fires that flared up on March 6, 2017 in Oklahoma, Kansas, and Texas. This article is part two of a three part series. It covers the relative humidity conditions in Oklahoma leading into this horrendous fire day.

AgBlog.Fire and dead grass.Kathy Larson and Joe Coffey.The Cayenne Room.Oregon (1)

March kicked off with relative humidities unusually low across Oklahoma. Continue reading

February’s Weather Role in NW Oklahoma Complex Fires (part 1 of 3)

Intense, devastating fires flared up one week ago in Oklahoma, Kansas, and Texas. This article is part one of a three part series. It covers the long-term conditions leading into this horrendous fire day. Part One covers weather factors in February that contributed to extremely dry conditions in Beaver, Harper, and Woodward Counties.

2017-03-07.NW OK Complex Fire.fire and truck line at night.Carmen Fire Dept 2

(Photo: Carmen Fire Department 3/7/17)

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2016 Monthly Air Temperature Review

What did you think of 2016? Was it a hot year? A cooler than average year? Would you believe that the summer was close to average?

Where the heat really came in was the spring and fall. Those were the seasons that climbed way above average.

For the year, 2016 was slightly warmer than the long-term 15-year Oklahoma Mesonet average from 2001-2015. Putnam and Minco were the warmest locations at 3 degrees above their average air temperatures. Most of the eastern side of Oklahoma was 2 degrees above average. In the west, most Mesonet sites were 1 degree above average.

2017-01-05.2016 Avg Air Temperature Continue reading

Frigid Oklahoma Cattle Comfort

What a cold weekend we just went through! For Oklahoma, the cold air swept through the state on Saturday, December 17, 2016. The next two mornings, Sunday and Monday, were especially brutal for cattle.

Checking the Mesonet Cattle Comfort Advisor for Saturday, the maximum Cattle Comfort Index values ran from 82 degrees at Broken Bow in the southeast to zero at Boise City and Eva in the Panhandle.

2016-12-17.cattlecomfort.warmest
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