CYS: The cap is eroding…but storms are still sub-severe. Looking at CI products

Forecaster comments from EWP blog...

Working the Cheyenne CWA, we have been waiting for the cap to erode, and it has started to during the past hour.  So far, though, the storms have been tame.  Monitoring the CI products reinforces that thought.  The upper right panel in the image below shows the instantaneous cooling rate at cloud top.  Most of these have been at the rate of -10C per 15 minutes.  This is roughly half of the typical rate that one might see as a precursor to severe storms.  While the convection is weak so far, we have potential for more interesting rotating storms later.

CI products: UAH strength of signal scheme in upper left, instantaneous cloud top cooling rate in upper right, accumulated cooling rate in lower left, ice cloud mask in lower right.

Nearcast CAPE over CO

The new CAPE field from the Nearcast (top image) output is depicting a nice area of instability with values ranging from ~1800 to 2000 J/Kg in NE CO and SE WY.  This area matches well with the SPC mesoanalysis MLCAPE (bottom image) axis extending into the same area.  Forecasters are currently monitoring the area for CI with the UAH SATCAST and UW Cloud-top Cooling rate products.  Expectations from the simulated satellite imagery are for rapid storm development to occur in the next hour.

GOES-15 Super-Rapid Scan over NE Colorado

GOES-15 SRSO was called to support the DC3 campaign over NE Colorado today.  CIRA has provided us with a web link that we are sharing with the forecasters in the HWT.  The link to the imagery can be found here...

http://rammb.cira.colostate.edu/templates/loop_directory.asp?data_folder=dev/lindsey/loops/goes15&image_width=1020&image_height=720

CYS: Convective Initiation and Impacts to Aviation

Forecaster comments from EWP blog...

Today is a great opportunity to test the Simulated Satellite products! I created a 4 panel to compare the sim sat products with the real time IR. I also overlaid jet routes to get a better picture of the potential impacts to aviation. One downfall to using the jet route overlay in AWIPS is that unless you’re familiar with the routes, you have no idea what you’re looking at. Maybe some day we can get a mouse-over feature with the jet routes so that the user can identify the names of the jet routes.

Figure 1: SimSat Compare with Real Time IR (lower left)

Figure 1 is the 4 panel comparison of the simulated products and real time IR. Figure 2 is the simulated IR and water vapor with jet routes overlaid. You can see that at 22Z, should the forecast be right, that re-routs will definitely be in order! I am eager to see how accurate this product is today…this could mean great things for the CWSU/FAA folks! Figure 3 is just a zoomed in 22z Sim Sat WV forecast.

Figure 2: 22z SimSat Forecast

The image in the lower right is the 10.4-12.3um IR which can help to show areas of low level moisture (yellow). As the column continues to moisten, you’ll see the areas of blue develop. Blue areas indicate a difference of zero.

Figure 3: Convective Initiation Forecast and BOU Impacts

Stay tuned to see how well the Simulated Satellite products work out!

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.