textproduct: Raleigh

WHAT HAS CHANGED

* Updated Aviation discussion

KEY MESSAGES

As of 300 AM Tuesday...

1) It will become progressively hotter through Independence Day, then less so with increasing chances of convection Sun and Mon.

DISCUSSION

As of 300 AM Tuesday...

KEY MESSAGE 1... It will become progressively hotter through Independence Day, then less so with increasing chances of convection Sun and Mon.

A strong mid and upper-level high/anticyclone will build across the TN and OH Valleys, then progress across and offshore the southern Middle Atlantic late week through the holiday weekend.

Historically, the most significant heat waves in cntl NC occur when the position of the ridge is centered from the TN Valley to the srn Appalachians. In this case, while strong, the position of the ridge to the north of the latitude of cntl NC for most of the period will favor the hottest temperatures from VA and NJ to the srn New England coast, while tropospheric-deep ely flow will likely prevail over cntl NC - at least until the ridge dampens and yields a light wly component by Independence Day.

It will nonetheless turn hot later this week and continue through the holiday weekend. High temperatures are expected to increase from mostly mid 90s Wed, to mid to upr 90s on Thu, then upr 90s to lwr 100s Fri-Sat. Heat index values will be a few degrees higher at times but not excessive, given only modest afternoon humidity levels during the period, regulated by mixed dewpoints in the 60s, to even 50s possible over the wrn Piedmont on Sat. In fact, with non-NBM, high-biased temperatures and dewpoints reflected with this forecast cycle, forecast heat index values remain below 105 except for just marginally above in the Coastal Plain and northeast Piedmont Fri- Sun. As such, no headlines are anticipated for at least the next few days.

Although the ridging aloft is forecast to weaken and break down over the Carolinas by Independence Day, the underlying airmass will probably not cool much until convection and diabatic cooling are introduced Sun and Mon, with added cooling with the possibility of a backdoor surface frontal passage by Mon.

AVIATION /18Z TUESDAY THROUGH SUNDAY/

As of 1249 PM Tuesday...

24 hour TAF period: VFR conditions will prevail across central NC through mid afternoon Wednesday. Some very isolated showers may develop across the far western Piedmont later this afternoon although they should remain away from INT/GSO and should be of no impact. What BKN/OVC cloud cover exists across the Triad sites should dissipate shortly after sunset, followed by mostly clear skies thereafter. Winds will remain northeasterly through the period, becoming light/vrb overnight.

Outlook: VFR conditions expected through at least Saturday. A potential return to more unsettled weather is expected late this weekend with localized reductions in cigs/vsbys where storms develop.

CLIMATE

All-time High Temperature Record and Most Recent Date of Occurrence:

KGSO: 104/1914-07-27 KRDU: 106/2024-07-05 KFAY: 110/1983-08-21

Record High Temperatures:

July 1: KGSO: 99/2012 July 2: KGSO: 98/1954 KRDU: 101/1954 July 3: KGSO: 98/1911 KRDU: 101/2012 KFAY: 102/2019 July 4: KGSO: 98/1970 KRDU: 101/9999 KFAY: 98/2019 July 5: KGSO: 98/2012 KRDU: 106/2024 KFAY: 101/9999

All-time High Minimum Temperature Record and Most Recent Date of Occurrence:

KGSO: 80/2007-08-09 KRDU: 80/2025-07-18 KFAY: 84/1928-06-22

Record High Minimum Temperatures:

July 2: KGSO: 76/2018 KRDU: 78/1931 KFAY: 77/1931 July 3: KGSO: 76/2018 KRDU: 79/2023 KFAY: 76/2023 July 4: KGSO: 73/2018 KRDU: 79/1902 KFAY: 78/1913 July 5: KGSO: 74/1999 KRDU: 78/2024 KFAY: 77/2005

RAH WATCHES/WARNINGS/ADVISORIES

None.