textproduct: Raleigh

WHAT HAS CHANGED

* No significant changes from earlier forecasts.

KEY MESSAGES

As of 250 PM Monday...

1) Except for Tuesday, highs are expected to be in the 90s everywhere for the next week, bringing danger to those who lack adequate cooling.

2) Diurnally-driven thunderstorms will be possible throughout the next seven days, with the lowest chances on Thursday and the greatest chances on Saturday.

DISCUSSION

As of 250 PM Monday...

KEY MESSAGE 1... Except for Tuesday, highs are expected to be in the 90s everywhere for the next week, bringing danger to those who lack adequate cooling.

Tonight will be the coolest night out of the next seven, with lows ranging from the mid 50s in the northeast to 70 in the southwest. Similarly, Tuesday will be the coolest day out of the next seven. The Triad will be on the cool side of the front, so highs will be in the mid 80s, while locations to the east should generally be around 90 degrees.

After the surface high pressure moves off the mid-Atlantic coast on Tuesday, warm and moist southerly flow will return to the region as ridging will start to build to the west. This will allow temperatures to rise generally into the low-to-mid 90s on Wednesday and increase further in to the mid-to-upper 90s on Thursday and the upper 90s on Friday. The probability of high temperatures reaching or exceeding 100 degrees on Friday is between 10-30% for the majority of the US-1 corridor and east. The experimental HeatRisk is showing the majority of central NC under a Moderate to Major risk of heat-related impacts from Wednesday through at least Sunday, with a few locations showing an Extreme risk of heat-related impacts on Friday and Saturday. This will also be made worse by above normal temperatures overnight. Lows look to remain in the low-to-mid 70s each night, allowing for little relief from daytime temperatures. However, the chance for isolated to scattered showers and thunderstorms may also provide some relief from the hot afternoon temperatures each day.

KEY MESSAGE 2... Diurnally-driven thunderstorms will be possible throughout the next seven days, with the lowest chances on Thursday and the greatest chances on Saturday.

A back door cold front is currently oriented from northwest to southeast across the forecast area. While the front has moved across the area today, it will take its time drifting to the southwest through the rest of the afternoon and overnight. The front should serve as a focus for showers and thunderstorms to develop, with the precipitation expected south and west of the Triangle. While RAP SBCAPE will range from 1000 to 3000 J/kg, a lack of wind shear will limit the potential for severe thunderstorms. However, DCAPE values approaching 1000 J/kg could allow from strong winds. By sunset, a slight chance of showers will continue west of I-74, but conditions should dry out by midnight. The front will move little Tuesday and Tuesday night, and rainfall will generally remain west of the Triangle, with showers/storms likely in the Triad.

The warm/moist airmass will remain overhead from mid-week through the weekend. A daily pattern of isolated to scattered diurnally induced showers and embedded thunderstorms looks to return to the region Wednesday through the weekend. The typical summer-like pattern is currently low predictability in exactly where showers may develop each afternoon. However, rainfall amounts look to be relatively light, with the 50th percentile of the LREF showing less than 0.1 inch of rain each day through Friday. This weekend, forcing will increase slightly as a front looks to fall apart as it approaches the area which may allow for slightly higher rainfall totals and potentially more organized storms. The LREF is showing up to 0.25 inch of rain on Saturday and an additional 0.1 inch on Sunday.

AVIATION /18Z MONDAY THROUGH FRIDAY/

As of 130 PM Monday...

TAF period: Much of the TAF period should have VFR conditions at all terminals. A front has moved into the area from the north, and while it will not do much to cool temperatures, it will serve as a boundary for scattered thunderstorms to develop this afternoon. Maintained the inherited PROB30 groups for MVFR TSRA at INT, GSO, and FAY where the greatest coverage is expected - no showers/storms are expected at RDU and RWI. Cumulus is increasing this afternoon, and should become more of a mid level stratus deck overnight. Confidence is increasing that INT/GSO will have MVFR ceiling restrictions late tonight, with a good chance of IFR ceilings even possible, but with models showing a tighter moisture gradient, removed the MVFR TEMPO groups at RDU and RWI, and just going with high MVFR at FAY. Wind will primarily be out of the east this afternoon and tonight, eventually veering to the southeast Tuesday morning. Gusts up to 20 kt will be possible this afternoon.

Outlook: Diurnally driven thunderstorms will be in the forecast through Saturday. Coverage will be the greatest at INT/GSO on Tuesday and Wednesday, with overall coverage decreasing Thursday and Friday before increasing again on Saturday. It appears likely that all sites will drop to MVFR in restrictions late Tuesday night and Wednesday morning, but after that, restrictions will likely be linked to locations where rainfall occurs.

CLIMATE

Record High Temperatures:

June 8: KFAY: 101/2008

June 10: KFAY: 99/2008

June 11: KGSO: 98/1914 KRDU: 100/1914 KFAY: 102/1926

June 12: KRDU: 98/2002 KFAY: 99/1926

June 13: KRDU: 100/2002 KFAY: 99/2022

June 14: KGSO: 98/1926 KRDU: 97/1944 KFAY: 100/2022

Record High Minimum Temperatures:

June 9: KGSO: 72/2020

June 10: KRDU: 76/2020 KFAY: 77/2020

June 11: KGSO: 74/2008 KRDU: 74/2008 KFAY: 77/1981

June 12: KGSO: 72/1998 KRDU: 75/1986 KFAY: 76/2016 June 13: KGSO: 73/2015 KRDU: 75/2025 KFAY: 77/1998

June 14: KGSO: 71/2025 KRDU: 79/2022 KFAY: 77/2022

RAH WATCHES/WARNINGS/ADVISORIES

None.