Dryness increases as summer heat lingers

Shaun Everston
Posted 7/28/17

A localized thunderstorm brought a bit of relief from July heat and dryness Saturday, delivering half an inch or more of rain south of I-80 and about 0.20 to 0.30 inches north of I-80.

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Dryness increases as summer heat lingers

Posted

KIMBALL – A localized thunderstorm brought a bit of relief from July heat and dryness Saturday, delivering half an inch or more of rain south of I-80 and about 0.20 to 0.30 inches north of I-80.
Conditions remained quite sunny and hot over the last week with the mercury topping 100 in many locations across the tri-state region and running solidly into the 90’s elsewhere.
Most locations across the Panhandle received at least some rain over the last week. Quantities were somewhat on the low side but the rain was still beneficial to rangeland, pasture, and dryland crops.
Across the region, summer rainfall has been very short in June and July. Kimball has received an average of 5.22 inches during those two months over the last 123 years. Rainfall this year in June and July totaled just 1.52 inches.
Fortunately, heavy rain and snow in May, totalling 4.6 inches, allowed surplus soil moisture to accumulate. This allowed good cool season grass production despite a dearth of rain, and the recent rainfall arrived in time to boost warm season grass production.

Regional Forecast and Conditions
As of Tuesday, July 25, sunrise temperature was 70 degrees under partly cloudy skies. A slow moving weather front was beginning to pass, promising widespread thunderstorms in the afternoon and evening and a high temperature of 94 degrees. Wednesday-Friday daytime temperatures were expected to be slightly cooler, with highs climbing only into the mid-80’s, and an increased chance of widespread thunderstorms across the region. Saturday-Wednesday daily high temperatures were once again forecast to reach into the mid- to upper-80’s, with overnight lows falling into the upper 50’s.
The coming week is expected to generate widespread afternoon and evening thunderstorms with areas of locally heavy rainfall possible. Skies are expected to be sunny to partly cloudy.
Air temperatures warmed across the region last week. At Kimball the July 18-24 daytime high averaged 93.57 degrees, about 5 degrees warmer than the previous week.
The weekly high temperature was 100 degrees on July 19. Overnight lows averaged 61.42 degrees, about 4 degrees warmer than the previous week. The weekly low temperature was 57 degrees on July 23. The weekly mean temperature was 77.5 degrees, about 5 degrees warmer than the previous week, and nearly 6 degrees warmer than the July average of 71.8. The long term average high and low temperatures at Kimball for July are 87.4 and 56.1 degrees, respectively.
Precipitation was reported at 12 of 13 Panhandle stations over the July 18-24 period, ranging from 0.02 at Harrisburg, Sidney 0.9 N and Sidney Municipal to 1.83 inches at Gordon. Dalton reported zero precipitation. Panhandle precipitation averaged 0.34 inches compared to 0.14 inches last week.
Panhandle soil temperatures ranged from 5 degrees cooler to 5 degrees warmer over the July 18-24 period: (this week/last week/change): Alliance 81.0/79.1 (+1.9) degrees; Gordon 78.7/82.6 (-3.9) degrees; Mitchell 82.9/87.9 (-5.0) degrees; Scottsbluff 82.1/81.0 (+0.9); and Sidney 86.5/81.5 (+5.0) degrees.
Winds near Kimball averaged south-southeasterly and occasionally quite gusty over the July 18-24 period. Gusts for the week averaged 29.85 mph. High gust for the week was 48 mph on July 22.

July 28 Weather Almanac
Last year – July 28, 2016: Daily high temperature 85 degrees, overnight low 57 degrees, average temperature 71 degrees. Precipitation 0.13 inches, snowfall zero inches, snow depth zero inches.
The warmest July 28 on record was 105 degrees in 1933. The coolest high temperature was 59 degrees in 2013. The coldest overnight low was 46 degrees in 1993. The warmest overnight low was 65 degrees in 1951. Since 1893 the high temperature for the date has averaged 86 degrees, the overnight low 57 degrees, the daily average 71.4 degrees, precipitation has averaged 0.10 inches, snowfall zero inches, snow depth zero inches.
The highest precipitation total was 2.10 inches in 2007.

U.S. Drought Monitor
The High Plains: Locally heavy rains fell in southern parts of the High Plains, with more than inches reported at several stations in southeast Colorado and southern Nebraska. A few stations in the Dakotas and Kansas received an inch or more of rain this week, but the showers and thunderstorms were spotty and amounts varied significantly. Most stations in the region were drier than normal this week with many receiving a tenth of an inch of rain, if any.
With daily temperatures exceeding 90 degrees F, the seven-day average maximum temperature was above 90 in a band from Montana to Kansas. The excessive heat increased evapotranspiration, as reflected in the extreme ESI and EDDI values, and further dried soils which were already parched.
According to July 17 USDA reports, topsoil and subsoil moisture was short to very short across 88/80 percent (topsoil/subsoil) of Montana, 85/79 percent of South Dakota, 65/58 percent of North Dakota, 65/57 percent of Nebraska, and 62/58 percent of Wyoming.
The heat and dryness have ravaged crops, with 61 percent of the spring wheat crop in poor to very poor condition in Montana and 40 percent in North Dakota. In South Dakota, 74 percent of the spring wheat was in poor to very poor condition, 38 percent of the corn crop, 33 percent of soybeans, and 45 percent of sorghum.
The pasture and rangeland statistics (in poor to very poor condition) were 74 percent for North Dakota, 68 percent for South Dakota, 58 percent for Montana, and 26 percent for Nebraska. As noted by the North Dakota State Climatologist, the spotty rains might have been enough to green-up the vegetation, but not enough to increase the vegetative volume.
Reports from the field include many reports of extensive drop damage, livestock water holes drying up, and cattle losing weight due to poor or nonexistent grazing land. The South Dakota State Climatologist reported that corn is in tasseling stage now; under drought stress, this can lead to an 8 percent yield loss per day, which is the highest rate of yield loss of any crop stage.

The agricultural impacts were compounded by low streamflows. According to the Bureau of Indian Affairs, the Ft. Peck and Ft. Belknap Tribes in Montana declared disaster emergencies in June that remain in effect; the Rocky Boy’s reservation, south of Havre, is experiencing drastic water shortages; and several Tribes in the eastern part of Montana have enacted
burn bans.
With many indicators, such as SPI, EDDI, ESI, and soil moisture, converging to exceptionally dry conditions, spots of D4 were added to the USDM depiction in Montana and North Dakota. D0-D3 were expanded in the Dakotas with collateral expansion in adjacent states (Nebraska, Iowa, and Minnesota). D0-D1 were expanded in Nebraska and Kansas, but D0-D1 were trimmed in other parts of Nebraska and Kansas where an inch to several inches of rain fell.
National Summary: An upper-level ridge of high pressure dominated the western contiguous U.S. during this U.S. Drought Monitor week. The ridge inhibited precipitation and kept temperatures warmer than normal across much of the West. Weekly mean temperatures were as much as 8 degrees warmer than the long-term average from the Southwest to northern High Plains.
Pacific fronts and weather systems rode over the top of the ridge, taking a northerly track which brought them across the drought-plagued northern Plains then into a trough over the eastern CONUS where they stalled out over the Southeast.
Monsoon showers developed in the Southwest, bringing above-normal precipitation to some areas, and small but intense storms developed with the fronts as they moved across the northern and central Plains. Only a few of these storms brought above-normal precipitation to the Plains. Summertime convection and frontal lifting brought rain to parts of the southern Plains and areas east of the Mississippi River.
The prolonged and intensifying drought ravaged crops and rangeland in the northern Plains, while soils continued to dry out across the West, Plains, and into the Mid-Atlantic region. Exceptional Drought (D4) returned to the USDM map this week as spots of D4 developed in the northern Plains where below-normal rain fell, and D0 expanded in parts of the Southwest where the monsoon precipitation was below normal. Persistent below-normal precipitation and enhanced evapotranspiration due to excessive heat expanded areas of drought and abnormal dryness in the central Plains to Midwest.

U.S. Conditions and Weather Report
A broad ridge of high pressure over the continental U.S. resulted in above-normal temperatures nearly nationwide, with cool conditions limited to the upper Great Lakes region and the Pacific Northwest.
Clouds and rain showers helped to slightly suppress temperatures across parts of the Deep South. Weekly temperatures averaged at least 5 degrees above average across large sections of the country, stretching from the Great Basin to the Plains and middle Mississippi Valley. Another area of heat covered the middle and northern Atlantic States.
Some of the hottest weather, relative to normal, blanketed the central Plains, where temperatures locally topped 110 degrees. “Ring of fire” thunderstorms prevailed around the periphery of the ridge, as moisture associated with the Southwestern monsoon circulation became entangled with Northern cold fronts.
Excessive rainfall totalling four inches or more caused local flooding in parts of southern Wisconsin, northern Illinois, northeastern Iowa, and southeastern Minnesota. Widespread showers also dotted the remainder of the northern Corn Belt, maintaining generally favorable conditions for corn and soybeans.
Farther south, hot, mostly dry weather dominated areas from the central and southern Plains to the mid-South, increasing stress on rainfed summer crops. Meanwhile, widespread showers across the lower Southeast and the Four Corners States contrasted with dry weather in California and the Northwest.
At week’s end, more than three dozen large wildfires remained active in the West, with the destructive Detwiler fire in Mariposa County, Calif., having burned at least 75,000 acres and more than five dozen homes.
Elsewhere, scattered showers provided limited relief on the drought-ravaged northern Plains, with the heaviest rain falling in parts of the Dakotas. However, in areas that did not receive much rain, high temperatures caused further deterioration in the condition of rangeland and crops.

USDA Weekly Weather and Crop Reports

Colorado
Hot and dry conditions across much of the state last week continued to advance crop development and winter wheat harvest.
Some areas received needed moisture, while others remained very dry. In northwestern counties, a reported lack of rain and hot daytime temperatures have driven irrigation and livestock water supplies to critically low levels; stream flow has been adversely affected as well as pond levels. One reporter noted haying is about two weeks early due to a lack of irrigation water in
the area.
In northeastern counties, reporters noted that hot and dry conditions continue to prevail although scattered precipitation was received last week. A reporter in Weld County noted that rain showers stalled wheat harvest for an afternoon last week. In these counties, irrigated crops remain in good condition where water supplies are adequate; dryland crops and pastures are quickly deteriorating with the lack of moisture.
In southwestern counties, reporters noted that monsoon season has begun with accompanying rainfall. Where moisture has fallen range conditions showed improvement, although some areas remain dry. Reports from Montezuma County indicated heavy rain damaged crops in some areas this past week.
In the San Luis Valley, localized rain was received last week, along with very isolated hail. Potatoes are reportedly doing well. Barley is quickly starting to turn, although some previous freeze or hail damage has shown up. A reporter noted that alfalfa weevils are still a problem in areas with some producers treating to mitigate.
Scattered rain was also reported across southeastern counties last week. Overall, hot and windy conditions have caused issues keeping irrigated crops wet. A reporter noted that alfalfa condition has declined since some irrigation water has been diverted to corn.
Statewide, winter wheat harvest was ahead of the average by week’s end.
Stored feed supplies were rated 2 percent very short, 6 percent short, 80 percent adequate, and 12 percent surplus.
Sheep death loss was 4 percent heavy, 63 percent average, and 33 percent light. Cattle death loss was 3 percent heavy, 66 percent average, and 31 percent light.

Nebraska
Temperatures averaged four to eight degrees above normal for the week ending July 23 with measureable rainfall reported in northern and southeastern portions of the state.
Topsoil moisture supplies rated 31 percent very short, 40 short, 29 adequate, and 0 surplus. Subsoil moisture supplies rated 24 percent very short, 42 short, 34 adequate, and 0 surplus.
Winter wheat harvest was wrapping up for the region. There were 6.4 days suitable for fieldwork.
Corn condition rated 5 percent very poor, 10 poor, 24 fair, 49 good, and 12 excellent. Corn silking was 76 percent, near the 78 percent reported at the same time last year and the five-year average of 74 percent. Dough was 9 percent, near 11 last year and 12 average.
Soybean condition rated 5 percent very poor, 10 poor, 26 fair, 53 good, and 6 excellent. Soybeans blooming was 79 percent, ahead of 72 percent last year, and near the 75 percent average. Setting pods was 26 percent, ahead of 16 last year, and equal to average.
Winter wheat harvested was 93 percent, near 90 last year, and ahead of 77 average.
Sorghum condition rated 4 percent very poor, 5 poor, 28 fair, 48 good, and 15 excellent. Sorghum headed was 10 percent, behind 22 last year and 23 average.
Oats condition rated 2 percent very poor, 3 poor, 37 fair, 50 good, and 8 excellent. Oats mature was 96 percent. Harvested was 76 percent, ahead of 63 both last year and average.
Alfalfa condition rated 6 percent very poor, 15 poor, 33 fair, 38 good, and 8 excellent. Alfalfa second cutting was 96 percent complete, ahead of 90 last year and 83 average. Third cutting was 22 percent, near 19 last year.
Dry edible beans condition rated 5 percent very poor, 12 poor, 25 fair, 41 good, and 17 excellent. Dry edible beans blooming was 58 percent, behind 74 last year, but ahead of 48 average. Setting pods was 12 percent.
Pasture and range conditions rated 14 percent very poor, 20 poor, 39 fair, 24 good, and 3 excellent.
Stock water supplies rated 6 percent very short, 13 short, 81 adequate, and 0 surplus.

Wyoming
Wyoming experienced warmer than normal temperatures for the week. All of the 34 stations reported at or above average temperatures for the week with the high temperature of 105 degrees recorded at Torrington and a low of 37 degrees at Lake Yellowstone.
Four stations reported no precipitation and Sundance had the most precipitation with 1.24 inches. Twenty-eight of the 34 stations received less than normal precipitation.
A reporter from Northwest Wyoming indicted that the spring rains brought on good grass which is now drying out, bringing on fire
danger concerns.
A reporter from North Central Wyoming noted that they have had a hot weather pattern with over 90 degrees, wind, and no measurable rain. They also indicated that water supplies are becoming short and farmers are preparing for harvest.
A reporter from Western Wyoming stated that it has been hot and dry with some thunderstorm activity but not much moisture.
A reporter from South Central Wyoming reported continued hot and dry conditions with pastures drying up. They also indicated that hay harvest is in full swing with production below average.  Another reporter from South Central Wyoming noted that water supplies are drying up and producers are pulling livestock off summer pastures early due to poor grass nutritional value and/or a lack of grass.
A reporter from Southeast Wyoming indicated that there has been some rain, but most areas received little moisture and hot, dry conditions persist.
Stock water supplies across Wyoming were rated 6 percent very short, 15 percent short, and 79 percent adequate.