textproduct: Aberdeen

KEY MESSAGES

- A dangerous and prolonged heat wave will continue through this week with temperatures and heat index values warming into the triple digits each afternoon.

- A Heat Advisory remains in effect for north central, central, and portions of northeastern SD and west central MN through Thursday.

- Elevated fire weather concerns are possible Wednesday afternoon and evening mainly along and west of the Missouri River due to the combination of low relative humidity, gusty winds of 25 to 35 mph, and drying fuels.

DISCUSSION

Issued at 1242 AM CDT Tue Jul 14 2026

Not much of a change in the overall forecast with this persistent heat wave that will continue the rest of the week with the possibility of some relief early next week. Ridge remains overhead, which has flattened a bit across Canada as a shortwave tracks across the top of it. It will then amplify behind it this afternoon and evening, with the axis of the slightly negative tilted ridge over Alberta/Saskatchewan by 00Z Wednesday. Models then actually have the ridge tracking ever so slightly eastward (becoming neutrally tilted) and actually weaken a bit by the end of the week. It then amplifies once again and retrogrades over the western CONUS through the weekend with the CWA in northwest flow. With this ridge and ongoing mid level high beneath it, this will continue to produce sinking air with no chance of moisture through at least Saturday. Slight pops do return Sunday and early next week but remain at 20% or less with a potential weak low/front. Probability of 0.01" is only about 20-40% during this time per NBM for now.

At the surface high pressure remains to our southeast and a weak mainly west to east cold front/trough to our north through Wednesday before the associated low tracks east across the northern Plains by the end of the week. This results in winds overall out of the south/southwest bringing in a bit drier air with dewpoints by peak heating each afternoon ranging in the mid to upper 50s over central SD to the James River. Dewpoints remain a bit higher east of here through west central MN ranging in the 60s. This drier air will allow for heat indices to be near or even a bit cooler then the actual temps across central SD (still upper 90s to lower 100s) while the more humid air east of the James River will put heat indices several degrees above maxT's (with the exception of the Coteau that remain cooler). Warm bias continues in the NBM 5.0 as NBM 5.2 is only about a degree difference over central SD (higher confidence in achieving forecast highs) while east of the James River is 2-3 degrees resulting in lower confidence. The highest spread seems to still be over far northeastern SD/western MN. This warm bias and resulting spread between NBM5/5.2 continues through the end of the week. Continued the trend and lowered MaxT's a degree or two blending in Consshort for today's highs through Friday. With only a few locations reaching Extreme Heat Criteria Monday and both NBM 5.0/5.2 heat indices below 105, went ahead and dropped the Extreme Heat Warning over north central SD to a Heat Advisory. Even looking ahead heat indices of 100 only look to be spotty and less widespread for the rest of the week. However, will keep the ongoing Heat Advisory in place for now that continues through Thursday evening.

Lastly, with more of a southwest component of wind, min RH will range from 20-30% west of the James River, lowest along and west of the Mo River. Luckily winds will be weaker today therefore, less fire danger concerns. However, they do increase Wednesday afternoon, with gusts of 25 to potentially 35 mph, highest over Corson/Dewey and Jones/Lyman. Ongoing dry air results in RH dropping again between 20-25% and combining with the gusty winds may led to elevated fire danger concerns. With the lack of rain and geocolor satellite continuing to indicate drying fuels west river, a fire headline may be needed for counties west of the Mo River Wednesday afternoon. Will let the day shift pull the trigger on that if needed.

AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/

Issued at 1215 AM CDT Tue Jul 14 2026

Terminals KABR,KATY,KPIR,KMBG

VFR conditions will continue at all terminals through the next 24 hour forecast cycle.

ABR WATCHES/WARNINGS/ADVISORIES

SD...Heat Advisory until 10 PM CDT /9 PM MDT/ Thursday for SDZ005>008-010-011-017-018-021-033>037-045-048-051. Heat Advisory until 10 PM CDT /9 PM MDT/ Thursday for SDZ003- 004-009-015-016. MN...Heat Advisory until 10 PM CDT Thursday for MNZ039-046.