Weekly Weather Update and Outlook: Oct. 5, 2023
Week Ahead Outlook
A strong upper trough and associated cold front is moving through the state today (Oct. 6) and bringing us our first real shot of cool air this fall. Rainfall amounts from Oct. 5-6 were expected to be mostly under 0.10-inch — more likely just enough to spot up your car. Winds will be strong from the northwest on Friday afternoon and skies should start to clear along with a drop in relative humidity. Thus, there will still be some enhanced fire risk due to the higher winds and lower humidity levels.
The surface high will be displaced to our south by later Friday night, so winds will not likely be dead calm for most of the state. Cloud cover isn't expected but any unexpected stratus formation would limit the temperatures from crashing as much as currently forecast. Nevertheless, this air mass looks to be cool and dry enough for temperatures to easily drop below 40°F statewide and much of north central and western Nebraska are quite likely to have a light freeze Friday night. A light freeze is also somewhat likely in portions of northeast Nebraska and southwestern Nebraska as well under this scenario. The Lincoln and Omaha metros are more likely to be in the 34°F-37°F range but that is chilly enough for some frost if winds are light enough. Be warned though that if winds do go perfectly calm between 3-6 a.m. on Saturday morning, the air mass will be dry enough to let temperatures drop below freezing for all but the very far southeast corner of the state and for temperatures to be in the 26-28°F range as far southeast as Wahoo or Lincoln.
So my best advice is to follow the local forecast carefully in the next 48 hours and take appropriate measures with sensitive vegetation. For much of north-central and western Nebraska, a light freeze has often occurred by now and it's definitely not unusual to have already had a light freeze from Grand Island to Omaha in the first week of October either. So this is certainly not an historically cool air mass. It just is going to be a bit of a shock given how warm it was for most of the last week for most of the state. Temperatures look to rebound nicely by Sunday though the eastern sixth of the state may get a light dessert next Monday in the form of a glancing blow from another cold front. For more information on the frost/freeze climatology, visit the following page from the Midwest Regional Climate Center.
Storm System Next Week
The beginning of next week looks great for fall harvest or wheat planting, albeit a bit on the seasonally cool side in the eastern portion of the state. Next Tuesday looks just about perfect statewide, with warmest readings likely to be found in the southwestern part of the state. Models are starting to show some signal for a storm system moving into the High Plains region the middle of next week. However, there is still uncertainty regarding the exact timing, placement and directional movement of the surface low, and strength. The latest run of the ECMWF shows a surface low tracking across Kansas and then veering northeast toward the Great Lakes region, but that track has not been consistent from run to run in recent days.
Meteorology to English Translation: There's something out there but we don't know exactly what it will be yet.
Right now, it appears the Panhandle and the southern third of the state are favored for precipitation, with some chance it could be in the one to two-inch range. But I'd really like to see more consistency in the models before putting any real confidence in those amounts. We should have a much better idea of the storm track and possible precipitation amounts or impacts by the end of the weekend.
Recent Precipitation and Recent Record Heat
Most of the state had over half an inch of rain in the last week, which is a first in a good while. The exception was the western Sandhills down into the Imperial area, which generally saw amounts under 0.10-inch. The good news is big chunks of southeastern Nebraska picked up over an inch of rain, which was badly needed given the severity of the drought. This area also saw several days in a row with record heat over the last week with temperatures in the upper 80s to mid-90s and breezy south winds. Other big winners include Sherman County, Blair, O'Neill, and the area between Hay Springs and Gordon in northwestern Nebraska.
The following locations set record highs in the last week. For Lincoln, it was the first time with record highs on three consecutive days (with records that still stand) since June 1988.
- Omaha — Two days: Sept. 29, (95), Sept. 30 (94)
- Lincoln — Two days: Sept. 29 (96), Sept. 30 (96), Oct. 1 (94)
- Norfolk — One days: Sept. 29 (95)
- Grand Island — One day: Sept. 29 (95)
Soil Moisture and Drought Monitor Update
The precipitation earlier this week led to decent improvements in top layer soil moisture, according to SPoRT LIS. While these soil moisture maps should be interpreted with a grain of salt, I would say with confidence that most of the eastern half of the state is in better shape now than at this time last week. For anyone ready to plant wheat in southeastern Nebraska, this recent moisture was well timed, and hopefully ensures that a much better stand of wheat will come up this fall compared to last fall.
Root zone soil moisture is still not great in most of the eastern half of Nebraska, with particularly low values in the far southeastern part of the state where abnormal dryness was introduced on this week's U.S. Drought Monitor. This, of course, does not mean that the root zone in Richardson County has 2% of available water. But it does mean that the average soil moisture value over the modeled layers (0-10 cm, 10-40 cm, 40-100 cm) is in the second percentile. A good soaking next week would make a big difference though.
Crop Condition Update
Corn is at 86% maturity (8% points ahead of schedule). Corn harvest is progressing nicely at 22%, which is five points ahead of the five-year average. Soybean is ahead of schedule for dropping leaves at 95% and soybean harvest is 29% complete, which is a big jump from last week and two points ahead of the five-year average. Sixty-four percent of sorghum was mature and 14% had been harvested. Winter wheat planting is also ahead of schedule this year with 79% planted, 7% above the five-year average and a ~20-point increase compared to last week. Pasture ratings improved again this week with 53% G-E and 16% P-VP.