Precipitation chances and cooler weather
After a very warm start to the week, the state is currently enjoying cooler temperatures and lower humidity. There will be a chance for showers and thunderstorms this evening in western Nebraska but most places will remain dry. A more potent shortwave will move into the region tomorrow and will initiate showers and thunderstorms. Chances begin in central sections of the state earlier in the day but chances increase tomorrow afternoon into tomorrow night. Storms are likely to develop in South Dakota tomorrow afternoon and then slide southeast into Nebraska during the evening hours in north central and west central Nebraska and in the overnight hours in much of eastern and southern sections of Nebraska.
Rain likely continue into the day on Saturday, especially in the eastern third of the state. Precipitation totals through Saturday evening from the models have been a little inconsistent but much of the eastern half of the state will pick up at least some moisture and many places will get a half inch to an inch. With a slow moving trough remaining to our south, there will be chances of showers and isolated thunderstorms through Monday. With the rain chances and increased cloud cover in the eastern third of the state, high temperatures will be well below average- likely holding in the mid to upper 70's through Monday. Humidity levels will also remain on the higher side during the daytime hours this weekend and into early next week, which may be problematic for trying to curb diseases like southern rust. Temperatures this weekend will be warmer in western Nebraska but still below average for the latter portion of July.
Warming back up later in the week
By mid-week the slow moving trough will be moving out of the southern Plains and ridging will be back in place over the north central U.S. This will bring warmer temperatures back by Wednesday to the whole state, with hotter temperatures in the western side of the state. Temperatures will climb further Thursday into Friday and highs likely will be in the 90's statewide by Friday. Temperatures may even flirt with 100 in parts of northwestern Nebraska where drought conditions are worse. Dewpoints also will be on the climb in the eastern sections of the state, so expect heat index values to be well into the 90's or lower 100's by the end of the week in the southeastern quadrant of the state. The CPC does have the far northwestern portion of the state in the slight risk category for excessive heat later next week. The 8-14 day CPC temperature outlook shows warmer than average favored statewide, with better chances in the western half of the state. The ECMWF and GFS ensembles are both in agreement with the warm finish to the month across the state.
Storms next weekend?
The 8-14 day CPC precipitation outlook shows below average precipitation favored in western Nebraska and no signal for the remainder of the state. The ECMWF also shows drier than average conditions across western Nebraska and the remainder of the High Plains for the last week of the month. The GFS is a bit wetter in the Panhandle but drier in west central and central sections of the state. A look at a few recent runs of the ECMWF AI though shows a trough moving back into the western U.S. by the end of the week with an area of high pressure around Florida. This would set us up for favorable moisture return from the Gulf (especially eastern Nebraska) and the trough may give us the elements (wind shear, lapse rates, etc..) to help generate strong to severe thunderstorms in the eastern third of the state and the broader Central Plains and Western Corn Belt regions next weekend. It's a ways out so my confidence in this isn't super high. Nevertheless, it may be something to watch out for.
Drier east, wetter west
Over the past week the western half of the state has been in a favorable location to get "ridge riding" storms and indeed some beneficial precipitation has fallen in spots. But the better precipitation amounts were relatively isolated and most places had under half an inch. This area of the state also was hottest (for actual air temperatures) so the rain that fell likely was not enough to cover potential evapotranspiration. But it was still more rain than what most of eastern Nebraska has seen in the last 7-10 days, which is "nothing" for many locations. Mother Nature looks to be more generous to the east in the coming days and most places had ample moisture going into the recent dry spell, so it hasn't been much of a concern.
Hot, but not as bad as expected
There was plenty of heat in the state late last week and early this week with everyone getting their turn at being pretty hot. But the actual air temperatures were generally under forecast values, especially on Saturday and Sunday. Some, perhaps most of the discrepancy, was related to models underestimating how high dewpoints would be (because of the crops) and how much cloud cover there would be at times. Some could have been an overestimate of mixing from aloft. Regardless, temperatures generally stayed 3-5F under forecast highs everywhere last weekend. It still managed to get 100F on multiple days in places like Chadron, Scottsbluff, and Imperial. But the 104-108F that looked probable a week ago at this time never materialized. Further east the corn was up to no good on Sunday and Monday and dewpoints approached or exceeded 80F in parts of the eastern sixth of the state. This brought heat index values into the 110-120F range. Thankfully the heat was short-lived.
Drought and soil moisture update
Abnormal dryness was re-introduced to the rest of Banner and all of Kimball counties and it was also introduced across southwestern Dundy County. Moderate drought remains in place for a good chunk of the northwestern Panhandle and some areas in Sioux County are getting borderline on being in severe drought (D2). Soil moisture percentiles have dipped quite a bit in eastern Nebraska over the past week but not too concerning levels for the most part. Exception would be in parts of southern Nebraska along the Kansas border where soil moisture percentiles in the 15th-30th percentile are more common again after a brief hiatus after rains around the 4th of July.
NASS Crop Progress update
Condition ratings for corn came in at 78 percent good-excellent (G-E) against 6 percent poor-very poor (P-VP) while soybean checked in again at 77 percent G-E and 5 percent P-VP. Corn is well ahead of the 5-year average with almost 50 percent in the silking stage and 8 percent in the dough stage. Soybean blooming (72 percent) and pod setting (22 percent) are also advanced compared to the 5-year average. Sorghum is rated at 78 percent G-E against 1 percent P-VP and is on par for heading. Winter wheat harvest is progressing well ahead of average (70 percent complete) and made a huge jump with the drier weather last week. Oat harvest is 34 percent complete and are rated as 73 percent G-E and 2 percent P-VP. Pasture ratings of the season show 70 percent G-E against 6 percent P-VP. VegDRI continues to depict very good pasture conditions in the northern and eastern Sand Hills regions but poorer conditions in parts of the northwestern Panhandle where drought has developed. VegDRI also shows good conditions on crops across much of the eastern two-thirds of the state. Mild stress levels are depicted in Perkins and Chase counties and more severe less of stress are depicted in Scotts Bluff, Banner, and Dawes counties in the Panhandle.
Temperature and Precipitation Roundup
Attached is a .pdf's containing the maximum/minimum temperature, average temperature, number of days with maximum temperatures ≥95F, minimum temperatures ≥70F, degree days, and total precipitation for each Mesonet station over the period from July 7-13. Includes CoCoRaHS observer reports. Below are the temperature and precipitation extremes around the state over the past week.
Maximum Daily High Temperature: 103, Chadron Municipal Airport
Minimum Daily High Temperature: 77, York
Minimum Daily Low Temperature: 49, Bushnell 15S
Maximum Daily Low Temperature: 75, Lincoln Airport
Maximum Weekly Precipitation: 1.60", Tecumseh 1S
Minimum Precipitation: 0.00", Multiple Locations
Eric Hunt, University of Nebraska Extension
