Moved to MLB

Here is a nice example of the two CI products and a healthy storm that formed in Florida.  We had just changed CWAs so it was more a matter of going back and seeing what they said rather than using in real time but they do show indications of a rapidly developing storm. See the red 95% blob (UAH CI product) on first image, the UW cloud top cooling on 2nd and storm getting big on third.

20120515 – 2125z update 1st warning of the week

The first warning of the week was issued by the MLB team for a storm just northwest of MLB.  The MRMS and 3dVAR shows some indication of rotation with that storm between 3 and 6 km.

Updraft helicity and merged azimuthal shear layers and units are different.  How does one compare between the two?

Jim LaDue: EWP week 2 coordinator

Monitoring & Forecasting DVN Convection

Despite strong indications from the NSSL-WRF SimuSat imagery, convection in the DVN CWA has stayed rather benign.  The NSSL-WRF appears to have overestimated the low-level prefrontal moisture.

SimuSat Imagery at Top, IR Imagery at Bottom, valid 2100 UTC 2012-05-15
SimuSat Imagery at Top, IR Imagery at Bottom, valid 2100 UTC 2012-05-15

The GOES-R NearCast Theta-E Low vs. Mid-Level Theta-E image indicates very little destabilization ahead of the front (in fact, it actually indicates increased stability).  This is consistent with surface dewpoints in the 30s and 40s reported ahead of the front.

GOES-R NearCast valid 2030 UTC 2012-05-15
GOES-R NearCast Theta-E Difference valid 2030 UTC 2012-05-15

There have been a few cloud-to-ground lightning strikes just to the northeast, and the 3DVAR and MRMS data have helped to monitor the convection across multiple CWAs and on the edges of multiple radars.

3DVAR Analysis valid 2120 UTC 2012-05-15
3DVAR Analysis of Reflectivity, Updraft composite, 30 Minute Updraft Accumulation, and 1km/10km Divergence, valid 2120 UTC 2012-05-15
MRMS Surface Merged Reflectivity, -20C Reflectivity, VIL, and MESH valid 2114 UTC 2012-0515
MRMS Surface Merged Reflectivity, -20C Reflectivity, VIL, and MESH valid 2114 UTC 2012-0515

LWX 20Z

Being LWX today for another rather quiet day. Nearcast products and simulated satellite (and HRRR and 3dVAR) both showed marginal instability and a few air mass sort of thunderstorms and that is what has been happening.  It has let us see a few flashes on the pGLM products but not really enough to evaluate usefulness in warning situation. Image below shows nearcast theta e product in lower right (showing not much) and simulated IR in upper right showing spotty but unimpressive convection.  Left two panels are real IR & Vis sat showing that the simulated stuff not bad.  The CI products seem to be hitting areas that do end up as the small thunderstorms but not sure they are showing more than can be diagnosed by looking at the satellite imagery so not sure if I would warn on this product any more often than the satellite and radar alone but good quick check to make sure I am not missing anywhere I should be watching.

NSSL-WRF SimuSat Prompts Move to DVN

The simulated satellite imagery based off the NSSL WRF is handling a cold frontal passage in the Midwest quite well this afternoon.  The 2000 UTC comparison between the WRF “SimuSat” and observed IR image:

NSSL-WRF Simulated GOES-R IR Satellite (top) vs. Observed IR Satellite (bottom) at 2000 UTC 2012-05-15
NSSL-WRF Simulated GOES-R IR Satellite (top) vs. Observed IR Satellite (bottom) at 2000 UTC 2012-05-15

The NSSL-WRF simulated satellite imagery suggests that storms will erupt over the next hour:

NSSL-WRF Simulated GOES-R IR Satellite (top) vs. Observed IR Satellite (bottom) at 2100 UTC 2012-05-15
NSSL-WRF Simulated GOES-R IR Satellite (top) vs. Observed IR Satellite (bottom) at 2100 UTC 2012-05-15

This model output, combined with hits from the UAH Convective Initiation product in the Cu field along the front, has prompted the RNK group to shift domains to DVN for the rest of the afternoon.

Visible Satellite and UAH CI Product, 1932/1930 UTC 2012-05-15
Visible Satellite and UAH CI Product, 1932/1930 UTC 2012-05-15

Update: 2012 May 15 1954z

The western target is now growing enough cumulus to have one of the teams move west.  Brian and Stephen will be localizing to Davenport, IA CWA to take the best advantage of evaluating CI along the cold front.  CAPE is weak but lapse rates are high.

Tags: None

RNK 19:15UTC

Although this was outside of our CWA, the CI product did a nice job of detecting a developing storm along the sea breeze front on the Carolina coast.  At 18:15UTC, CI indicated a 90% (red) area.

45 minutes later, at 19:00, the visible image showed a full-blown storm with a wide anvil.

Weak Convection in the RNK CWA

We are monitoring convection in the RNK (Blacksburg, VA) CWA this afternoon, but so far the development has been rather weak.

The 3D-VAR analysis has been useful for monitoring updraft intensity and anticipating possible stronger updrafts (top-right indicates instantaneous updrafts, bottom-right indicates 30-minute updraft history).  However, none of the strong updrafts have maintained themselves beyond one “scan”.

RNK 3D-VAR valid 1900 UTC 2012-05-15
RNK 3D-VAR valid 1900 UTC 2012-05-15

The convective initiation algorithms have struggled due to all of the cirrus blanketing the northwestern half of the RNK CWA, but some clearing in the southeast has produced some CI from the UAH algorithm.  Using the new Strength of Signal output, nothing has gotten above ~50 (the included sample is just 46 in the south-central portion of the CWA), and indeed there has been little significant development in those areas.  Nothing has triggered the UW Cloud Top Cooling algorithm yet in our area as of 1902 UTC.

Convective Initiation Algorithms valid 1845 UTC 2012-05-15
Convective Initiation Algorithms valid 1845 UTC 2012-05-15