Allen, NE Weather

This Hazardous Weather Outlook is for northwest Iowa, west central Iowa, southwest Minnesota, northeast Nebraska, central South Dakota, east central South Dakota, south central South Dakota and southeast South Dakota.

Day one

Tonight.

Scattered showers and thunderstorms will continue to move northeast through the overnight. Severe weather is not anticipated.

Days two through seven

Saturday through Thursday.

A second round of very light showers is possible Saturday night into Sunday morning.

Sunday night and into Tuesday a stronger low pressure system looks to bring widespread accumulating rainfall to the region. An inch or two of rain is possible in total. At this time flooding is not expected. Now would be a good time to clean those gutters of leaves and debris if you haven't already done so.

Spotter information statement

Spotter activation is not expected at this time.

NWS Sioux Falls will discontinue the Hazardous Weather Outlook product (HWO) on November 8, 2026. Weather hazards and outlooks will continue to be provided through other standard NWS products, including weather briefing packets, forecast discussions, weather story graphics, the graphical hazardous weather outlook, and updated hazard messaging. All local products and visual tools are accessible directly at: weather.gov/siouxfalls.

Key messages

- Showers and very isolated thunderstorms will continue tonight into Saturday morning. No severe weather expected.

- A more widespread rain returns later Sunday night into Monday night. The latest guidance suggests about a 60-90 percent chance for more than an inch of rain. Flooding is unlikely, but not zero. Additional rainfall is likely on Tuesday.

- A low confidence threat for low topped supercells Monday afternoon and evening in far southeast SD, northeast NE and northwest IA.

Update

Issued at 855 PM CDT Fri Oct 30 2026

The forecast remains on track at issuance of this update. Light scattered showers and thunderstorms will continue to move northeast through the remainder of the overnight. Rainfall amounts are expected to remain low with only a trace up to a tenth or two. Soundings indicate most of the region will become near saturated to saturated in the boundary layer. This will result in very low stratus to fog formation overnight. Ensemble guidance indicates around a 30% chance for visibility to fall to 2 miles or less at times. Near sunrise showers should begin to taper off, stratus begins to lift, and any fog dissipates. Most of the day will then be dry. Skies look to remain mostly cloudy, however surface WAA on breezy southerly winds will warm afternoon highs into the upper 50s to low 60s. Afternoon gusts of 15-25 mph will taper off after sunset.

Saturday evening and through the overnight a southern stream short wave works northeast into the area. This will bring another round of scattered, very light showers. Some weak elevated instability may allow for a few lightning strikes as well, but severe weather is not anticipated. Once again only a few hundredths to a tenth or two is expected. Showers taper off through the morning and Sunday afternoon should be dry. Diurnally breezy southerly winds will once again usher in mild WAA boosting highs into the 60s for most of the region.

Late Sunday evening a much stronger upper trough will push into the region from the west, bringing widespread chances for accumulating rainfall overnight and through Monday. For more details on this system please refer to the Discussion below.

Discussion

Issued at 148 PM CDT Fri Oct 30 2026

Showers remain likely tonight into Saturday morning as low level moisture deepens, roughly the lowest 5 km, and marginally dry, cooler air above this layer allows for weak instability, generally 200-500 J/kg CAPE. This should generate mainly showers, but a few lightning strikes will be possible. Rainfall amounts will mostly be light, but some pockets of a tenth of two will be possible.

Saturday night into Sunday should be mostly dry, but moist neutral soundings and lingering moisture/cloud cover may allow for some patchy drizzle and showers. Overall low impact, but likely not an entirely dry period.

A fairly well agreed upon trough of low pressure will move onto the Plains Sunday night, deepening on Monday as a strong southern stream jet strengthens. This should provide that area with widespread rainfall and if everything comes together timingwise, the threat for an isolated tornado over southeast parts of the area.

All models continue to indicate a widespread 1-2" of rainfall from Sunday night into Tuesday morning. Very little disagreement for the most part on timing and location of the rainfall. Given a fairly wet pattern the past 6 weeks or so river flooding could start to become a problem. But for now, the latest hydrologic modeling suggests at least 2.5-4" of rain would be needed to push rivers to action stage and minor flooding, so for now chances of river flooding are pretty low (<20 percent). Also suggestions that 1.5" of rain in an hour could produce some localized flash flooding, but for now the rainfall rates should not be quite that high. All in all, it looks like a band of warm advection rainfall will lift northward Sunday night into Monday. Later Monday afternoon into Monday night a dry slot could move in and if convection does not develop, a dry period or period of drizzle will be possible. Then later Monday night into Tuesday wrap around rainfall will move through.

While this is a very low threat probability, we will need to keep an eye on the development of surface low pressure Monday afternoon as the upper level wave moves through. Starting to see indications this surface low pressure could end up near southeast SD/northwest IA which could bring about a threat for some low topped supercells/isolated tornadoes. The 6z ensemble data has the EC placing this SFC low in southeast SD late Monday afternoon while the GEFS and Canadian Ensemble are in eastern NE. Obviously a big difference so trends will need to be monitored. The 12z GFS is now placing the surface low in southeast SD late Monday afternoon as well.

Tuesday will likely see some wrap around rainfall continue, but should diminish throughout the day. Wednesday through Friday should be mostly dry and cooler with highs from the upper 40s to mid 50s.

Aviation

Issued at 1129 PM CDT Fri Oct 30 2026

A mix of MVFR down to LIFR will prevail for the first half of this period. Scattered showers and thunderstorms will continue to move to the northeast through the overnight, gradually tapering off through mid-Saturday morning. Low stratus and possibly patchy fog lingers into Saturday afternoon before ceilings begin to lift to MVFR, and possibly up to low VFR along and east of I-29 Saturday late afternoon and evening. Additional chances for scattered light showers return late Saturday evening.

Light southeast winds will gradually increase after sunrise and become southerly. Breezy afternoon gusts of 20-25 kts are expected for areas west of I-29, generally 20 kts or less to the east. Winds decrease after sunset but remain on the breezy side with gusts around 15-20 kts through the end of the period.

Watches, warnings and advisories

SD: None. MN: None. IA: None. NE: None.