A severe weather episode is expected over our Washington DC Lightning Mapping Array (LMA) domain, so we will be operating in that area.  An upper level trough and associated surface cold front over the central Appalachians, along with a tongue of very moist unstable air to the lee of the mountains are the primary ingredients for severe weather today.  0-6 km shear will exceed 30 kts over the domain, and increase to above 40 kts over central and northern Pennsylvania.  0-1 km shear will be adequate (20 kts), and CAPE will be in the 1000-2000 J/kg range.  A lee trough has set up, and the first wave of severe thunderstorms is expected to affect our CWAs (Sterling VA – LWX, and State College PA – CTP) around 20 UTC, and should be through around 23-00 UTC.  Unless severe weather is ongoing in two CWAs after dinner, we will break off two of the forecasters to do the 5/24/08 archive case, while the other two will remain issuing warnings and watching the GOES-R products.  Otherwise, we will conduct the archive event on Thursday in an afternoon shift with two forecasters, and an evening shift with the other two forecasters.

Greg Stumpf (EWP Weekly Coordinator, 14-18 June 2010)

We are planning to work the event that is highlighted with an SPC Moderate Risk in Central Indiana south through central Kentucky and there already as a Severe Thunderstorm Watch in effect.  There is sufficient deep layer shear, as well as some decent low-level shear for rotating storms, but the main threat today appears to be high wind.  This will be a good example of how we might be able to use some of the MRMS products for wind warnings, which we haven’t had much experience with yet this spring.  So we will start with localizations for Indianapolis IN (IND) and Louisville KY (LMK).

In addition, the GOES-R convective initiation products should get a good work out today, as the area covered by both CWAs is essentially cirrus free at the moment!

Greg Stumpf (EWP Weekly Coordinator, 14-18 June 2010)

Today we start week 9 of the 2010 EWP.  Our visitors are Angela Lese (WFO Louisville, KY), Melissa Kreller (Southern Region HQ, Fort Worth, TX), Marcus Austin (WFO Tallahassee, FL), and Dave Sharp (Melbourne, FL).

A long stationary front is draped across the southern plains, with a late season strong 500 mb jet max overhead.  This will provide severe weather and flash flooding opportunities from a broad region from the south Texas plains through central Oklahoma.  SPC highlights the area with a Slight Risk, and best chances of supercells over the Texas portion of the risk area where the deep layer shear is more adequate.

Because central Oklahoma is under the convective gun today, we opted to operate within the Lightning Mapping Array (LMA) network there.  Unfortunately, the morning flash flood over OKC (10″+) have caused some outages in the LMA netork, and thus it is unavailable.

Therefore, we are going to complete training through 530pm, break for dinner, and then do a short IOP focused on the 5% SPC tornado risk in Texas.  Most likley, we will act as WFOs Lubbock, Midland, San Angelo, or Norman (the latter, for the NW TX counties).

Greg Stumpf (EWP Weekly Coordinator, 14-18 June 2010)