textproduct: Sioux Falls

KEY MESSAGES

- QUIET AND MILD: Dry conditions and above normal temperatures continue early this week with highs in the 50s and 60s.

- MINIMAL RAIN MID-WEEK: The only precipitation chances in the next 7 days will occur late Tuesday night into Wednesday, but any rain will be very light and unimpactful.

- COLDER AIR AHEAD: A strong front drops temperatures significantly Thursday and Friday, though temperatures will gradually warm above normal by next weekend.

UPDATE

Issued at 825 PM CST Sun Nov 8 2026

A quiet night continues across the area! Temperatures have fallen off quickly after sunset, with some spots having already dropped into the upper 30s. Current thinking is that temperatures should drop more slowly and/or remain largely steady as we head throughout the remaining overnight hours as southerly flow increases. Can't rule out some fog mainly in and around river valleys wherever winds can turn calm early tomorrow morning. But with the slightly elevated winds, do expect any fog to remain patchy in nature.

A mid level wave passes through the area tomorrow morning, leading to an increase in cloud cover. Some of these clouds may form within the DGZ mainly over southwest Minnesota, but ample dry air below should prevent anything from reaching the ground. Can't entirely rule out a sprinkle, but chances are very low (<20%). Cloud cover Monday will play a role in how warm we get during the afternoon. Currently looking for clouds to break up through the afternoon hours as the wave passes to our east and drier air filters in. In this most likely scenario, we will warm into the low to middle 60s for highs on Monday. However, if clouds linger a bit longer than expected, temperatures may only rise to the upper 50s to right near 60. Still above average either way!

DISCUSSION

Issued at 1202 PM CST Sun Nov 8 2026

THIS AFTERNOON: A beautiful Fall day continues across the region as we're seeing plenty of sunshine, temperatures above normal, and generally light winds. In fact, the latest NBM continues to be a few degrees too cool for highs, so have adjusted upwards. This trend likely continues Monday as well.

TONIGHT: Weak southwesterly surface winds will develop later this evening and continue overnight. While broad warm advection continues above the ground, there may be some potential for valley/river fog into Monday morning. The general increase in mid- upr clouds could temper this potential somewhat.

MONDAY-TUESDAY: Extremely quiet weather continues early this week. A frontal boundary will swing southeast across the Tri-State area early Monday morning, turning a light southwesterly wind towards the west-northwest in the afternoon. Not a ton of cold air behind this boundary, so anticipating highs rising into the 60s in most locations. High pressure passing through the Plains Monday night shifts southeast of the area by Tuesday. Additionally sfc cyclogenesis over the Western High Plains will aid in inducing a southwesterly boundary layer flow on Tuesday. Temperatures will again rise into the upper 50s in most areas. One area to watch in this timeframe would be a repeated risk for valley fog Tuesday morning as winds may be very light and the low-lvl ridge remains west of the CWA. HRRR/RRFS both indicate increased potential for lowered visibilities.

TUESDAY NIGHT-WEDNESDAY: The only PoPs in the 7 day forecast are focused in the late Tuesday night and Wednesday timeframe. A progressive open shortwave leaves the Pacific Northwest and reaches the Plains Tuesday night. This moisture starved wave could lead to a few sprinkles into Wednesday morning. A deeper upper trough centered over Hudson Bay will allow a second shortwave to pivot southward out of central Canada and into the Plains on Wednesday. Again not a ton of moisture with this system through the column, but perhaps a brief window early Wednesday where sprinkles to a very light rain shower will be possible. Ensemble probabilities remain low, with measurable rain chances between 20-40%, and probabilities of >0.10" near zero. NBM probabilities are likely too low, which is understandable given spread in models. Either way, not a highly impactful system.

THURSDAY-SUNDAY: Arctic high pressure arrives into the Plains for Thursday. This 1033 mb high pushes a shallow but meaningful drop in temperatures southwards, with highs on Thursday favored to be in the lower 40s Thursday and Friday. Some of the coldest air of the fall season may arrive Friday morning with lows potentially in the lower to middle 20s. 25/75th percentile data from the LREF suggests a wider range of possibilities (>10 degree spread) west of the James River which is the result of uncertain low-lvl warm advection return.

Mid-lvl heights grow through next weekend, with strong indications of a continued dry forecast through Sunday. Temperatures will also begin to rise after the arctic high passes likely at or above normal. A 15 degree spread in the 25/75th high temperature forecast through the weekend may be the result of some uncertainty on the eastward progression of the mid-lvl ridge and continued influence of cooler SE surface flow. Regardless, near to above normal temperatures are favored.

AVIATION /06Z TAFS THROUGH 06Z TUESDAY/

Issued at 1104 PM CST Sun Nov 8 2026

A strengthening low level jet will result in LLWS concerns for a few hours across the area tonight into tomorrow morning. Patchy valley fog can't be ruled out through about 09.14Z, but widespread issues are not expected and dense fog is unlikely. Southerly winds will turn more northwesterly as we head throughout the day today as a weak cold front moves west to east across the area. Winds turn light and variable Monday evening. Highest wind gusts (around 20-22kts) this morning will be in south-central South Dakota and over the higher elevations of the Coteau des Prairies. Then in the afternoon, these higher gusts will be mainly over just south-central South Dakota.

FSD WATCHES/WARNINGS/ADVISORIES

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