The 2013 EWP was held for three weeks in May, with 6 participants per week attending from Eastern, Central and Southern Regions. I had the opportunity to attend in the third and final week. Unfortunately, many issues arose during my week which affected the initial timeline/plan laid out for us to follow. The first of two EF5 tornadoes to hit the OKC area ravaged Moore, OK on the Monday. We also were limited on the tools to test Wed-Thurs with the loss of GOES-14.
The test bed was arranged to where there were two forecasters on a meso desk for the duration of the shift each day. They would provide hourly updates on the environment or determine if the area of concern needed to be shifted. There were then two teams of two who were given responsibility of different CWAs and providing warnings for their respective area.
Timeline for the Week
Sunday – Arrived in Oklahoma.
Monday – Introduction to the test bed, overview of the week, discussion of expectations for the week. The Moore tornado occurred at the beginning of this shift and with many people helping to run the test bed being affected by the storm (i.e. their kids in the path) along with technical issues we were dealing with, there was a lot of confusion to the first day, limiting to what we were able to accomplish. We were unable to use any of the test bed products in real time to analyze the tornado that occurred, though we were able to go back later in the evening and analyze the day.
Tuesday – Warning Operations over Fort Worth and Shreveport CWA early on, followed by Albany CWA in the evening.
Wednesday – Warning Operations over Buffalo and Binghamton CWA.
Thursday – Warning Operations over Amarillo, Lubbock, San Angelo and Midland CWA.
Friday – Week wrap up, with a 30 minute national call discussing things learned during the week.
Lessons Learned
With a shortened testing period this year, each week was asked to analyze all the tools to be tested, though focusing on two primary areas. We presented nationally for the “Tales of the Testbed” webinar on the last day covering these two specific topics, discussing best practices and how we found we could utilize in the tools in our own office operations. The focus for my week covered the Multi-Radar Multi-Sensor (MRMS) and the Hail Size Discrimination Algorithm (HSDA). In addition to the tools/experiments, we were asked to provide feedback on the usage of AWIPS 2 and the whole warning generation.
Mesoscale Analysis Tools
There were two things we were asked to utilize in determining the mesoscale situation. Unfortunately, these tools are restricted to their domain of Oklahoma and Northern Texas and that general vicinity. However, talking with the representative for the LAPS forecast, I was informed that they eventually would like to spread to the rest of the country, depending on the success they find in the southern Central Plains.
OUN-WRF and LAPS 1km and 3 km forecasts cannot be utilized up here in the Northeast. However, the LAPS 2.5 km analysis is available to be used at this time. I found during our warning situations that using the Theta-E values from LAPS was a best practice in figuring out where the convection was going to initiate and continue to form. The ability of AWIPS2 to allow multiple layers to be easily overlaid and the easy access with zooming in and out without constantly having to reload the frame allowed the forecaster to analyze the situation at a much quicker pace as well as obtain a much clearer picture. I found it beneficial overlaying the analyzed 2.5 km CAPE values with the latest reflectivity images then comparing to how the LAPS 1 and 3 km forecasted these parameters over the next few hours. Overall, the LAPs had the better grasp of the type of storm development and the location though the timing was off by up to 1-2 hours. It also is run at 15 minute intervals, allowing a more up to date version of what is occurring. The OUN-WRF had a better handle of the timing of the development, but was off on the location.
I would really like to see the forecasted LAPS in our region of the country as it proved quite useful in determining where the most likely area of convection would be. In addition, in discussing other potential uses, the LAPS rep informed me they have found it useful in forecasting the rain/snow line, producing fairly accurate forecasts, during winter events which would also be very useful in the Northeast.
Convective Initiation Tools
Unfortunately I wasn’t able to test these tools as well as the other experiments. On Tuesday, we arrived after initiation had begun, so we were unable to do any pre-event analysis. On Wed, we lost these tools when the GOES-14 satellite was down and our warning domain was outside GOES-13’s track. Luckily Thursday we were able to analyze the CI tools for the storms that occurred over northern Texas, allowing some familiarity but not as much as I had hoped. One side note I would like to make, I have been analyzing these tools available via the web to see how each handle CI here in the Northeast. For the couple of convective events we have had in the past few weeks, I have found that the CI tool has given about 1 hour lead time for areas further inland, but is still having issues with capturing the potential for convective development along the coast. One issue these tools do have is cirrus contamination and this was noted in several areas we were analyzing during the test bed.
Warning Tools
The experiments that were the focus of the week were the MRMS and the HSDA. The incorporation of the MRMS and HSDA will be very beneficial in warning operations. These products combine data from multiple sources, doing a QC over the data and then producing a final result that depicts a clearer image of what is actually occurring, compared to the usage of just one radar/source.
One of the more interesting aspects of the MRMS was the ability to use something other than reflectivity and velocity to create your warning polygon. For the issuance of tornado warnings, using either the 30 minute or 60 minute tornado track allowed the forecaster to see the trend of rotation, the strength of it as well as the path it was taking. While we may have to have four panels or more up to see rotation throughout the vertical column, using the rotation track products allowed us to see general rotation strength in the lower levels as well as in the mid-levels, just by looking at two screens. The color coding of the product also gave us an indication of the severity of the situation and caught our attention easier than diagnosing an all-tilts product. The same concept was used with the MESH tracks which allowed the forecaster the ability to see the track of the hail core producing severe hail as well as enabling the forecaster to just look at one product (or multiple depending on the time scale) versus having to have an all-tilts up, which takes space and time. One other aspect I found very beneficial with the MRMS was the ability to set up a four panel screen with reflectivity at the 0oC, -10oC and -20oC compared to the lowest level reflectivity scan. This allowed for a quicker diagnosis to determine if severe hail was being produced within the hail growth zones. All the while too, because these products are incorporating many different sources, it also allows the forecaster to not to have to trouble themselves on bringing up all the surrounding office radars in addition to their local radar. This could help in saving memory space within AWIPS, allowing for the program to run quicker as well as general diagnosing time for the forecaster.
The HSDA products also provided quite valuable in determining the hail potential of a storm. Once it is determine if an area of the storm is possibly producing hail, the use of the HSDA then informs you of the potential size of it. We had great success in verifying the large versus giant hail in the storms of the southern Central Plains. Unfortunately, we were able to use the product for the storms here in the Northeast due to a misunderstanding of the use of the product. But I would be curious to see how well the storms verify compared to the HSDA in storms up here as well.
AWIPS2
Overall, I had great success utilizing AWIPS2 into the warning operations during the test bed. The one main issue that occurred when I was producing warnings was that if a warning polygon happened to overlap into a different CWA when I was first constructing it, even after hitting the Warned/Hatched Area button, it still issued the full polygon that overlapped into the other CWA. This was presented to the IT rep during the test bed to hopefully be corrected. Otherwise, the functionality of AWIPS2 really did speed up the analysis as well as warning process.
Ashlie Sears
General Forecaster
NWS Upton NY (New York City)
2013 Week 3 Evaluator