textproduct: Aberdeen

KEY MESSAGES

- Rain continues this morning, coming to and end from west to east this afternoon and evening. An additional half an inch of rain is expected along and east of I-29. West of the highway, between a tenth and a quarter of an inch of rain is still to come.

- Northerly winds increase Monday afternoon, with gusts of 35 to 45 miles per hour possible. The strongest gusts are currently expected over the James River Valley. Winds will diminish Monday night as low pressure continues off to the east.

- High temperatures 5 to 15 degrees below normal expected through the middle of the week. Highs are expected to be in the upper 40s to 50s through that period.

UPDATE

Issued at 1223 PM CDT Mon Apr 27 2026

Updated aviation discussion below.

UPDATE Issued at 939 AM CDT Mon Apr 27 2026

Made some minor changes to the forecast for today, mainly to increase pops based on radar trends.

UPDATE Issued at 639 AM CDT Mon Apr 27 2026

See below for an aviation forecast discussion for the 12Z TAFs.

DISCUSSION

Issued at 229 AM CDT Mon Apr 27 2026

Rain is ongoing this morning due to a Colorado Low ejecting into the northern plains. As of 06Z, the Codington/Hamlin/Clark County area has seen the most rain, roughly 1"-1.25" over the past 24 hours according to MRMS estimates (which matches up well with observations so far this morning). Expecting a brief lull in the rain early this morning, although the persistence of low clouds may continue to support some drizzle. Rain will begin once again between sunrise and noon this morning (depending on location). Rain is expected to end over central and north central South Dakota this afternoon, lingering over northeastern South Dakota and western Minnesota through the evening. The latter area has the highest remaining rainfall totals expected, around half an inch (with perhaps locally higher amounts up to three quarters of an inch) through tonight. Values decrease moving west, around a quarter of an inch still expected over the James River Valley and central South Dakota, down to around a tenth of an inch still to come over north central South Dakota.

As the low pressure center moves off to the east, a northerly low- level jet will move into northeastern South Dakota this afternoon. Up to roughly 40 knots will be possible at 850mb, which will mix to the surface under the well-mixed boundary layer this afternoon. Latest guidance has shown a downward trend in the strength of the winds aloft, and therefore the strength of the winds at the surface. Latest probabilities from the NBM give a 10-30% chance to see gusts at Wind Advisory levels (45 mph), the highest chances located over the James River Valley. McPherson County in particular boasts the best chances, and if anywhere needs a headline, that would probably be the place. However, the NBM is by far the most enthusiastic about gusts, and other short term ensemble guidance (namely HREF and REFS) show less than a 10% chance through the afternoon. The cold air advection behind this system also does not appear to be overly strong, which limits some of the concern that model guidance is underdoing the gusts. Therefore, no headline will be issued for strong wind gusts this afternoon at this time.

An upper-level trough will sit over the northern plains through mid- week, allowing colder air into the Aberdeen CWA. 850mb temperatures at or near freezing sit between the 10th and 25th percentiles for this time of year, which translates to highs in the 50s through Thursday, roughly 5 to 15 degrees below late-April normals. There will be some chances for rain to develop Wednesday and Thursday afternoons due to jet streaks moving overhead on the back side of the trough. There is still some uncertainty as to the development of these showers, and a drier near-surface layer may limit the ability of developing rain to reach the surface. With both of those considerations in mind, there is low confidence in any significant accumulation on either Wednesday or Thursday afternoon at this time.

Pattern will transition to an upper-level ridge moving into the area for the weekend. This will bring about a return to near-normal to slightly above normal temperatures through the weekend. This pattern will not be favorable for precipitation development, with little chance through the weekend.

AVIATION /18Z TAFS THROUGH 18Z TUESDAY/

Issued at 1223 PM CDT Mon Apr 27 2026

Terminals KABR,KATY,KPIR,KMBG

A storm system is producing IFR cigs for all terminals. Drier air should move into the area later this evening and through the overnight with VFR flying conditions expected. Northerly winds with gusts exceeding 25-30 knots will slowly subside later this evening as well.

ABR WATCHES/WARNINGS/ADVISORIES

SD...None. MN...None.