textproduct: Des Moines

KEY MESSAGES

- Relatively warm temperatures and early morning patchy fog for the first half of the week.

- Low chances for precipitation (15-30%) and gusty winds Wednesday into Thursday.

- A cooling trend with sub-freezing morning lows possible Thursday through end of the week.

SHORT TERM /THROUGH TUESDAY/

Issued at 150 PM CST Sun Nov 8 2026

Clear skies are allowing temperatures today to climb into the upper 50s and low 60s today making for a great afternoon to be outdoors, at least for this time of year. The boundary layer is mixing at a greater depth than what most models anticipated, leading to higher mid-day temperatures and stronger wind gusts of 20-30 mph. The next two days will be a similar story regarding temperatures but high- based clouds lingering through the day tomorrow may dampen diurnal heating efficiency. Nonetheless, southwesterly low-level warm air advection should allow temperatures to climb to the upper 50s at the very least. The uncertainty of exactly how warm temperatures get tomorrow display well when comparing NBM guidance to the REFS ensemble and convective-allowing models (CAMs). The REFS and CAMs do not make it out of the upper 50s tomorrow, whereas the bias- corrected output from NBM easily approaches the mid-60s by 20z. Wind gusts tomorrow afternoon will again be breezy due to tightening surface pressure gradients across the area, which eventually move out and bring calmer winds Tuesday.

Patchy fog has been the trickiest part of the forecast with 5-10 mph surface winds keeping it isolated to low-lying valleys the last few nights. Winds will be calmer tonight and tomorrow night which could allow for greater fog development, but it is still not expected to be widespread. In fact, cloud cover (30-60% coverage) advecting in from the north/northwest late tonight and Monday night could disrupt nocturnal radiative cooling and thus hinder expansive fog development despite the calmer winds.

LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/

Issued at 150 PM CST Sun Nov 8 2026

Ensemble and longer range guidance continues to signal a longwave trough expanding over the central and eastern US through the middle of the week. Deterministic models are becoming confident in a shortwave trough sweeping through the state early Wednesday morning as this change in the weather pattern is ushered in. The associated surface low carries precipitation (15-30% chance) and gusty winds with it, but the exact magnitude, timing, and track of the low are still fairly uncertain at this time. Given temperatures cooling Wednesday night through Thursday, the potential for wintry precipitation is not out of the question. The rest of the week continues this cooling trend as northerly winds amplify cold air advection into the area.

AVIATION /18Z TAFS THROUGH 18Z MONDAY/

Issued at 1058 AM CST Sun Nov 8 2026

Winds this afternoon will be out of the northwest at 5-10 kts for KDSM/KOTM and 10-15 kts for KFOD/KMCW/KALO before diminishing after sunset. Main impacts include patchy fog in the vicinity of KDSM/KOTM and winds shifting to be southerly/southwesterly for all TAF sites overnight. Winds will become gustier (15-20 kts) by 17z tomorrow. VFR conditions expected throughout the period.

DMX WATCHES/WARNINGS/ADVISORIES

None.