textproduct: Aberdeen

KEY MESSAGES

- Hot temperatures and dry conditions are expected through the end of the week into the upcoming weekend with readings around 10 degrees above normal.

- A Heat Advisory remains in effect for central and portions of northeast SD today as afternoon heat index values top out around 100 degrees.

- A pattern change next week could potentially return temperatures closer to normal along with increasing chances for precipitation.

DISCUSSION

Issued at 316 AM CDT Thu Jul 16 2026

The main forecast challenge continues to revolve around the ongoing above normal temperature pattern most of us have been experiencing this week. More subtle changes are expected to take place during the next few days, but any noticeable differences from the current hot and dry stretch of days should be negligible. The upper ridge will remain centered just off to our south and southeast today, maintaining a significant influence on our weather. Another day of hot and dry conditions are expected as 850mb temps remain in the low 20s C east to the mid to upper 20s C west. Afternoon highs will reach the mid 90s to around 100 degrees across central SD while our eastern zones remain relatively cooler in the upper 80s to low 90s. Brought today's Max Ts more in line with the NBM5.2, which has handled daytime highs fairly well the last few days. Afternoon heat index values look to top out in the mid to upper 90s across the James Valley to the upper 90s to low 100s across central SD. WBGT values will be highest across central SD with readings in the mid 80s and the HeatRisk will reach the major category from the James Valley and points west. Based on some of these figures, decided to drop the Heat Advisory across northeast SD and west central MN but maintain it from Brown/Spink west through this evening. Guidance progs the thermal ridge to set up west of the James Valley today. Given some uncertainty on how far east this thermal ridge makes it this afternoon, took the conservative approach with the headline decision. Heat index values east of the James Valley don't even come close to Heat Advisory criteria. In fact, forecasted values this afternoon are more than 5 degrees cooler than the 100 degrees or higher criteria.

A weakness in the upper ridge will track across mainly ND later today and Friday. This will help bring an area of low pressure and associated frontal boundary into the western Dakotas this afternoon and into our northern and western zones on Friday. The persistent southerly low level flow will become northerly on Friday. Any moisture associated with this feature should remain in ND where the sfc low, warm front and better forcing track. High temperature projections on Friday will be dependent on the timing of the fropa. RAP/NAM suggests an earlier passage with some CAA getting underway during the afternoon hours across our northern zones while other guidance holds the thermal ridge in across most of the forecast area through peak heating in the afternoon. The air mass behind this front is not noticeably cooler by any stretch so am not expecting any noteworthy relief from the heat. Widespread daytime highs in the 90s to around 100 degrees are still expected with max heat indices in the mid 90s to low 100s in most areas. For now, will leave the current Heat Advisory headline in place but future shifts will have to consider extending it and resurrecting one across our eastern zones. Sfc high pressure builds southeast across eastern ND into MN Friday night through Saturday, glancing our eastern zones. Saturday might actually provide a brief break from the significant heat with forecasted highs projected to be in the mid to upper 80s east to the low to mid 90s west. As high pressure slips southeast of the area on Sunday, southerly flow returns as s/w ridging punches back northeast across the CWA. So, anticipate widespread 90s for highs in most zones with low 100s expected again across parts of central SD.

Longer range guidance continues to show a more noteworthy pattern shift across the Northern Plains as northwesterly flow aloft returns. A stronger upper trough is progged to shift southeast across the region early next week suppressing the upper ridge back across the Rockies and Southern Plains. Pcpn chances return by the end of the weekend into Monday and possibly beyond through the middle of next week as potential increases for some upper waves to traverse the region along associated sfc lows and frontal boundaries. Temperatures should begin to resemble more normal readings for late July by that time with highs in the low to mid 80s and overnight lows in the low 60s.

AVIATION /06Z TAFS THROUGH 06Z FRIDAY/

Issued at 1209 AM CDT Thu Jul 16 2026

Terminals KABR,KATY,KPIR,KMBG

VFR conditions are forecast through the TAF period, with south to southeast breezes persisting.

ABR WATCHES/WARNINGS/ADVISORIES

SD...Heat Advisory until 10 PM CDT /9 PM MDT/ this evening for SDZ003>006-009-010-015>018-033>037-045-048-051. MN...None.