Rotation track shows Eakley supercell track quite well. Latest base SRM suggests tornado now.
CI algorythms show CI further south.
Category: General
General Information and News
Somewhat messy convective mode over our domain in sw OK. But supercell evolution appears to be happening for three storms. Both CI algorithms predict CI over western N TX, but hasn’t happened yet. UAHCI is “hotter” than the CIMMS CI. Tail-end storm in eastern Kiowa county has no interference to its south. Motion will probably take it into the western OKC metro by 4-5pm.
Convective initiation along sw OK dryline
Convective inititation occured along the southwest OK dryline. According to UAHCI and CIMMS CI products, had about 10-15 minute lead time for storm near Altus. 30 minute lead time from UAHCI and 20 mintue lead time from CIMMS CI for storm near Sayer.
Horizontal convective rolls east of sw OK dryline suggest storms may form in the warm sector too…maybe!
Pablo, Rudoph, and Bobby
Ultimate CI
Visiting scientists and NWS forecasters visiting the EWP this week have begun looking at real-time data with the promise of some exciting weather over OK this evening. We are currently examining the SATCAST and UWCI products in combination with the multi-radar multi-sensor (MRMS) and PGLM products to anticipation convective initiation. The participants have worked together to develop what has been so lovingly called the “ultimate CI” 4-panel display within AWIPS. The 4-panel (shown above) includes the following products that are linked to the nowcast and detection of CI… Starting from top left and moving anti-cyclonic (clockwise) we have the visible with SATCAST, visible with UWCI, visible with MRMS reflectivity at -10 C, and finally visible with PGLM and NLDN lightning detections. The 4-panel has been saved as a procedure that forecasters can now load very quickly within their AWIPS D2D workstations throughout the rest of the week. Future visitors will have this available as well. This helps demonstrate the ability to combine these unique datasets from multiple sensors into one effective decision support tool.
Posted by Chris Siewert at 3:38 PM (from the GOES-R blog).
EWP 2011 Week #3
Week #3 is underway with our guest NWS forecasters: Jason Jordan (WFO Lubbock, TX), Daniel Leins (WFO Phoenix, AZ), Bobby Prentice (WDTB, Norman, OK), Pablo Santos (WFO Miami, FL), and Kevin E. Smith (WFO Paducah, KY).
Morning consisted of our normal Monday training session, followed by getting used to the new products on a displaced real-time case. As of 3:30pm, everyone has switched over to looking at real-time data, as convection is developing in western Oklahoma.
— Travis Smith, weekly coordinator
Live Blog 19 May 2011: 2334 UTC
After a brief excursion into the KS/NE region, we’re re-localizing back to OUN with our evening forecaster shift.
Week 2 :: Day 4
A good day for warning operations. Storms began initiating prior to the 1 pm discussion just south of Childress, TX. We jumped into warning operations immediately after our portion of the discussion.
At first, we had everyone issuing their own warnings at each workstation (minus the PAR corner which is being used to collect data). Unfortunately since we are all in the same CWA, everyone was seeing each others’ warnings. We then sectorized and had K Brown and Steve focusing on storms at I40 and North,
with Jessica, Bill and Kevin D focusing on the cells south of I40:
We will continue operations in OUN’s CWA, with an eye on Central KS for additional development of supercellular thunderstorms. If those develop, we will consider having a pair of forecasters move to that area.
-K Manross :: Week2 EWP Weekly Coordinator.
pGLM realtime comparison with MESH and 3D-Var Updraft
With warning operations already underway for western Oklahoma, forecasters are deep into their storm analysis.
One of the more interesting features they have been picking up on is the consistent signals between the pGLM lightning trends and values from the MESH algorithm as well as the 3D-Var derived updraft fields.
This was well illustrated by the storm north of Elk City moving from Beckham to Roger Mills county. At approximately the same time ~1900-1915 UTC, the lightning rate increased from 5 to 15 flashes per min (per pGLM grid box, not per storm) as MESH ramped up and updraft increased within the 3D-Var product. Shortly after this increase, both the pGLM and MESH values decreased with this storm (the 3D-Var updraft values also showed this, but with a bit of a time lag).
Also of note, prior to losing NLDN data, with the storms seemed to be producing relatively little CG lightning. In this case, the pGLM data was definitely giving a better view of the electrical activity and storm intensity. (1 to 1.75 in hail has already been reported across West and SW Oklahoma).
-K. Kuhlman (pGLM scientist, week 2)
19 May 2011 morning discussion
Area of focus will be KS/OK, where dryline convection is forecast by all high-res models. There are timing differences between SPC WRF, HRRR, and OUN WRF…with OUN WRF and HRRR convecting earlier. Late morning OA indicating that cap has weakened to under 25 j/kg along and east of dryline so initiation before 20z possible near and south of Red River. Later initiation expected farther north across west-central and northwest OK, and with diurnal backing and low-level jet intensifcation, early this evening, intensification and tornado potential will increase by 23/00z.
Primary area of concern will be northwest Oklahoma into south-central Kansas (OUN-ICT CWAs) where tornadic potential will be higher and overall coverage expected to be greater. Although instability will be substantial farther south, better shear/LCL values will be seen farther north across nw OK into srn KS. This idea, with much greater updraft helicity forecasts, is supported by OUN WRF. Any convection in SW OK/NW TX is fcst to occur fairly early with weak cap…but not develop particularly strong or rotating updrafts. Concern that if a large area fires too early that may limit additional convectiv e development over nw OK or s-central KS due to cirrus debris. Still…low-level jet strengthening by evening may be enough to help support stronger convection in KS.
18Z position of dryline is just east of DDC to GAG/CDS/SNK. Little in the way of eastward mixing is expected today given deeper moisture to its east and strong jet/ht falls to its west. If storms can get going over west-central and northwest Oklahoma, they should have a better chance of survival off/east of dryline with much better flow over that region.
Despite some degree of uncertainty in timing and exact locations for supercell development in the srn Plains today…high res model guidance and lack of jet cirrus are giving us more confidence that deep convection will in fact develop in a few spots along dryline compared to yesterday…and thus it makes sense to stay focused on the OUN/DDC/ICT CWAs throughout the day…rather than spending any time at all evaluating products in the mid-Atlantic, where shallow convection under persistent upper low is expected to fire again with diurnal heating. In fact some very shallow convection already occuring and overall severe threat looks very minimal there.
Shift to eastern Colorado 18 May 2011
19/0100Z: Supercells over Crowley and Kiowa counties. Kiowa county storm still shows strong/deep mesocyclone with attendant large hail/damaging hail risk. There was a brief land spout reported with storm early in life cycle, but appears that it has evolved into a more HP-type storm with decreased tornado potential. 0-2km Az-shear has weakened the past 30 minutes with this HP transition. Although MESH is indicating less-than-severe-size hail, there are reports of 1″ to 1.75″ hail with the Kiowa county storm. Hgt 50dbz above -20C and estimated dbz at -20C would support the larger hail. kbrown