textproduct: Raleigh

WHAT HAS CHANGED

As of 140 AM Tuesday...

* Increased Fire Danger Statement for the western Piedmont and Sandhills through 800 PM today.

KEY MESSAGES

As of 144 AM Tuesday...

1) Dry fuels combined with lower humidity and near record heat will promote fire weather concerns through the end of the week.

2) A highly anomalous mid-level ridge will persist over the southeastern United States through late week, supporting an early- season heat wave with temperatures 1520F or more above climatology.

3) Late-weekend pattern transition possible with low-end rain chances on Sunday with fropa...followed by cooler temps.

DISCUSSION

As of 144 AM Tuesday...

KEY MESSAGE 1... Dry fuels combined with lower humidity and near record heat will promote fire weather concerns through the end of the week. No changes to the week as far as highs in the upper 80s to lower 90s and no rainfall through Saturday.

The NC Forest Service has requested additional messaging along with their current state-wide burn ban. We issued an Increased Fire Danger Statement (IFD) the western Piedmont/Sandhills through 800 PM today. More statements will be needed Wednesday and beyond.

KEY MESSAGE 2... A highly anomalous mid-level ridge will persist over the southeastern United States through late week, supporting an early-season heat wave with temperatures 1520F or more above climatology.

A highly anomalous mid-level ridge will persist over the southeastern United States through late week, supporting record or near-record heat across central North Carolina. Both the GFS and ECMWF deterministic and ensemble guidance remain in strong agreement depicting a robust 500-mb ridge centered over the Southeast and Mid- Atlantic. During this period, H8 temps are progged in the 15-17C range along with deep-layer thickness values approaching summer-like magnitudes. As a result, high temps will reach the upper 80s to lower 90s basically Wednesday through Friday, with the typically warmer locations southeast of RDU possibly seeing mid 90s. These values are 20F degrees or more above mid-April normals. Hazards associated with this heat may include early-season heat stress (especially vulnerable populations) due to limited acclimatization. See the climate section below for more details about the records that may be threatened with this heat wave.

Key message 3...Late-weekend pattern transition possible with low- end rain chances on Sunday with fropa...followed by cooler temps.

The ridge will gradually weaken and shift east over the weekend as a trough advances from the Plains. A cold frontal passage is expected on Sunday which may result in low-end rain chances. Behind the front, temps will trend closer to seasonal normals (low-mid 70s) early next week.

AVIATION /12Z TUESDAY THROUGH SATURDAY/

As of 607 AM Tuesday...

Sub-tropical high pressure extending across the South Atlantic states will favor a high probability of VFR conditions through most of the week.

SSW surface winds that will strengthen and become occasionally gusty with daytime heating again today 10-20 kt. Winds will become light at 5-10 kt. tonight.

Outlook: Sub-tropical high pressure will favor warm, dry, and VFR conditions in cntl NC through Sat.

CLIMATE

All-Time Records for April

KGSO: 95 on 4/28/1915 KRDU: 95 on 4/23/1980 and 4/28/1896 KFAY: 96 on 4/12/1930

Record High Temperatures:

April 14: KGSO: 90/1922 KRDU: 91/1941 KFAY: 93/1922

April 15: KGSO: 90/2006 KRDU: 92/1941 KFAY: 95/2006

April 16: KGSO: 88/2002 KRDU: 92/1941 KFAY: 94/2006

April 17: KGSO: 90/1967 KRDU: 93/1896 KFAY: 92/1941

April 18: KGSO: 90/1976 KRDU: 95/1896 KFAY: 93/1941

Record High Minimum Temperatures:

April 15: KGSO: 65/2006 KRDU: 64/1993

April 16: KGSO: 66/2006 KRDU: 64/1912 KFAY: 69/1934

April 17: KGSO: 63/2002 KRDU: 67/1896 KFAY: 66/1921

April 18: KGSO: 66/1909 KRDU: 63/1941 KFAY: 67/2002

April 19: KRDU: 67/1896 KFAY: 67/2002

RAH WATCHES/WARNINGS/ADVISORIES

None.