DFW: 06 JUNE

Forecaster comments from EWP blog...

Cloud top cooling at 1745 showed evolution but it was already in place and immediately on radar.  Lightning flash density peaking over 50 flashes minute near Red River.  MESH got hail over 1 inch near Red River and we found we had KDYX which showed good rotation for storm along line.

BOU: OUN-WRF / Synthetic Satellite on Storm Initiation

Forecaster comments from EWP blog...

The above two images predict storm initiation at 19z. The top image is a 4-panel of WRF-derived synthetic satellite products and the bottom image is a single panel OUNwrf 1km agl reflectivity from roughly the same time. Both products show rapid thunderstorm initiation around 19-1930z. Given recent vis satellite imagery, this appears too early. Only time will tell…

EWP daily debrief 6/6

Yesterday was a rough day for the satellite products due to extensive cloud cover, but we were able to get some feedback from today's debrief with the EWP forecasters...

SATCAST / UW Cloud-top Cooling
- "There was a lot of cloud cover over the area, so there wasn't a lot of opportunity to use it (CTC)... but we did have one case over the ocean that worked very well and I would have issued a special marine warning for it."

Nearcast
- Forecasters did not find much utility in it yesterday due to ongoing cloud cover issues, especially over FL/GA.

PGLM
- Forecasters mentioned that they would like to have a value of total flashes in the upper corner of the AWIPS II display much like NLDN does... and if possible, a ratio of IC-CG as well.

OUN (LBB): CI with Boundary Interaction?

Forecaster comments from EWP blog...

Agitated cumulus on visible satellite noted over Childress County.  UAH CI values currently at 53, but have been steadily increasing the last few volume scans. Outflow boundary from western Oklahoma storms continues to push southwestward.  Watching to see if storms will develop if the boundary helps initiate convection. 21Z OUN WRF now showing a second line of convection developing along the southwest boundary. Stay tuned.

OUN: An Aviation Perspective…

Forecaster comments from the EWP blog...

The image below (Figure 1) illustrates the potential for convective initiation, using the UAH-CI tool. The high altitude jet routes overlaid with the CI and latest satellite data show the potential impacts to aviation. I expect that the CI tool will be very useful in operations – especially at the CWSUs.

Figure 1: Convective Initiation Impacts on Aviation

TMU is always asking about timing and location of convective development. Things become problematic when routes need to be changed at the last second as a result of developing thunderstorms. If we have more tools to provide a larger lead time, TMU personnel can plan farther in advance – which leads to saving money and time…and stress!

OUN: Don’t put all your chips into one [or two] products…

Forecaster comments from EWP blog...

One thing I’ve begun to wonder is will there be a loss of SA when a forecaster sees an area of “potential development”. The image below (Figure 1) illustrates the UAH-CI in the upper-left panel, while the upper-right panel shows the UW-CTC. My concern is that someone might see a CI area in the 60-70% confidence range and lose their sense of SA as they wait for further development…and the CTC algorithm to hopefully pick up on the developing storm.The UW-CTC product is designed to only pick up on the stronger development…which could easily lead to missing weaker convection. Not only that, but if any bit of the anvil goes near another developing cell…the algorithms will not pick up the newly developing thunderstorms…could end up to missing a warning.

OUN: CI products

Forecaster comments from EWP blog...

UAH Convective Initiation images showed a brief value of 65 in northeast Comanche County but the UW_CTC product never showed a cloud top cooling value. This seems to be due to the proximity of the cluster of cells to the west. The cell in northeast Comanche County was very slow to develop, but did become very strong and actually produced a 62 mph wind gust. Additionally, the MESH showed hail sizes of over one inch.

UAH signal at 1915z in NE Comanche Co.

Cell first noted at 1925z

One inch hail detected 45 minutes after initial reflectivity blob on radar, and 55 minutes after UAH signal.

Evaluation of UAHCI early on in MLB

Forecaster comments from EWP blog...

Looking across FL, much of the area was obscured by thick high clouds, making the CI products impossible to calculate/use. However, at 1710Z, the UAHCI algorithm did indicate possible CI just off the eastern FL coast, with a relatively low strength of signal of 30-40. Of note, the UWCTC algorithm did not hit on this cloud mass at all. As the follow image at 17:45Z shows, the band of clouds with a low SOS did not develop and actually diminished. This is within the expected outcome given the low SOS.

MLB: Checking out the RGB Airmass GOES Sounder product

Forecaster comments from EWP blog...

Thunderstorms over our region are fairly tame at the moment, so I began checking out some other interesting products.  Here is a shot of the RGB Airmass product produced by the GOES sounder.  GOES-R will have a similar image.  This basically takes information from four different wavelengths and combines them into one image.  Reddish colors here are high PV air associated with the jet…notice the band across the western Great Lakes.  Blue indicates a cooler airmass with associated midlevel clouds…notable across the northeast US.  Greenish colors are thicker low-level clouds with a more moist airmass…not surprisingly, the southeast US shows this.  Yellowish colors, such as over the Pacific Northwest, are low-level clouds in a cooler airmass.  White areas are deep cloud decks, often over convection, like Florida and the eastern Gulf.  Looping this product can show airmass movement and jet position/structure.  This can be useful as a check against NWP models.  I’ve posted both the RGB product (top) and the normal IR image at the same time (bottom) for comparison.

JAX:Cloud top cooling and marine supercells

Forecaster comments from EWP blog...

CTC and CI products have shown promise today despite shield of cirrus/anvil blowoff. The above image illustrates large CTC at 1910z.  Within 15 minutes of this image, a line of small discrete supercells developed just offshore.