EWP Blog

Westward moving sea breeze front helped to spark sporadic showers/thunderstorms during the afternoon hours. We captured the interaction of an already ongoing weak shower, as front moved in from the east.

The southern parts of Nassau and Charlton county and Baker county were monitored. At 1932Z an increase in cloud top cooling was noticed and 8 min later, CI product also had probabilities of 70 % plus for this area. At the same time, a cooling rate of roughly -15K/15 min was detected. Rapid development occurred thereafter with 50 dBz and more seen in the JAX radar side at 1947 Z, which gave a good lead time for focusing on the potential hot-spot over NE Florida. The storm was a pulsating one with rapid weakening thereafter.

Helge

The more I look at these products, the more I’m convinced they work very well in tandem with each other.  Given an environment that supports convective growth, a strong UAH-CI signal (upper image, top left panel) typically precedes a strong UW-CTC signal (middle image, top right panel).  In this case, the strong UAH-CI signal (1615 UTC) preceded the UW-CTC signal (1645 UTC) by about 30 minutes.  By 1715-1730 UTC, 30-45 minutes later, deep-moist convection did indeed form as evidenced by the numerous CG strikes (bottom image, bottom left panel).  We’ve seen this all week…UAH-CI gives us a heads up that general convection is initially building, then a short time later UW-CTC typically picks up on the stronger convection building.  Given a strong cap isn’t present and instability is sufficient, deep-moist convection typically develops 30-60 minutes thereafter.

Latest CI image shows moderately high probabilities for CI along ahead of the westward moving sea-breeze boundary.  Best chance for thunderstorms appears to be from the interior counties towards the west coast.  Some initiation is possible across Northern Brevard County…though the prospects for lightning are looking slim at this point.

HIRSCH

We’re currently monitoring the rapidly inland moving see breeze front over NE Florida with enhanced TCU present along the convergence zone, whereas the west coast see breeze has trouble to move inland within dominant easterly wind regime. Both convergence zones enter an area over N-C Florida where slightly lower dewpoints (lower to mid 60s) are present. With ongoing diabatic heating, cap continues to weaken or has already vanished with isolated initiation possible over N-C Florida in the following hours but ongoing large-scale weak subsidence seems to delay initiation a bit. HRRR quite aggressive with initiation mainly along the western sea breeze front with RUC also showing sporadic storms over N-C Florida. Overall set-up is not impressive and favors only the development of a few thunderstorms. Moderate CAPE and weak shear environment may result in a few strong and slow moving storms.

Neither CI nor Cld top cooling products showing robust signs for initiation … mainly over C Florida. Both products however show more vivid activity offshore over the Atlantic, where mid-levels remain a bit cooler.

Helge

Well anticipated by OUNWRF, strong to severe storms formed over E-C Colorado (here E of Pueblo) by 0030 Z. This is the latest forecast for 0200Z, showing the supercell moving straight to the east.

Below are DVIL images at 0058 UTC and 0107 UTC.  Left image is MRMS and right image is KOAX 88-D.  By 0107 UTC, the severe storm moved into the KOAX cone of silence, causing it to disappear, while the MRMS kept the storm’s integrity.