FA2521-18-Q-B091_Revised_31Aug18_PWS_Nocturnal_Lightning.pdf

PERFORMANCE WORK STATEMENT

FOR

UNEXPLAINED NOCTURNALLY FORMING LIGHTNING IN THE CCAFS/KSC AREA

Ver-2

(31 Aug 2018)

Revised 30 Jul 18

1. Title: Unexplained Nocturnally Forming Lightning in the CCAFS/KSC Area

2. Definitions: None

3. Description:

The 45th Weather Squadron (45 WS) provides comprehensive weather services to America’s space program at Cape Canaveral Air Force Station (CCAFS) and NASA Kennedy Space Center (KSC).

Lightning is one of the most impactful weather phenomena to CCAFS/KSC, especially via the lightning watches and warnings and forecasting and evaluating the lightning Launch Commit Criteria

(LLCC), which are a large set of complex weather rules to avoid rocket-triggered lightning to in-flight rockets. On rare occasions, thunderstorms form at night with no obvious cause. Although rare, these events can surprise 45 WS forecasters and lead to missed lightning watches, unpredicted LLCC violations, and unpredicted dangerous conditions.

This project is to determine how frequent unexplained nocturnally forming thunderstorms occur in the

CCAFS/KSC area, the conditions under which it occurs, and develop and test a prediction tool suitable for use in 45 WS operations.

The prediction tool will be a method or algorithm that can be implemented into an operational tool that can be implemented for use by the 45 WS, such as software on the Meteorological Interactive Data

Display System, or an EXCEL spreadsheet.

The tool shall apply only to the lightning season in central Florida, May-Sep. The method/algorithm shall use data only available in real-time to 45 WS before sunset for the night that immediately follows through the following sunrise.

The vendor shall consult with 45 WS on the appropriateness of the method/algorithm for operational implementation and data availability by 45 WS.

The prediction method shall include the use of the standard method separate development and test data to include all events, including null and occurring events.

If a categorical prediction method is developed, the verification and testing shall include the standard metrics of Probability Of Detection, Probability Of False Alarm, True Skill Statistic, Critical Success Index, and Bias.

If a probabilistic prediction method is developed, the verification and testing of the method shall include the standard metrics of a reliability diagram, sharpness diagram, RMSE, and Briar Skill

Score.

Deliverables: The project shall deliver the following:

a) An overall climatology of the unexplained nocturnally forming thunderstorms. This may be a map showing where the unexplained nocturnally forming thunderstorms formed in the

CCAFS/KSC area.

b) Stratified climatologies of the phenomenon. The stratifications should show if there are any of the following preferences: over the ocean or over land, time of night, any preferred time of day, time of year, formation conditions, etc.

Possible preferred formation conditions include:

i) The atmosphere being more unstable than normal, such as a range of K-Index specialized for this application,

ii) Occurrence of land breeze front

iii) Occurrence of southeast convergent lines affecting the CCAFS/KSC area, as discussed in the AMU report on that topic (see references below)

iv) Presence of more pockets of warm water temperature in the near Atlantic Ocean

v) And combinations of these factors, etc. The stratified climatologies may be maps and/or box and whisker plots of positive and null events along with hypothesis tests if there are statistically significant differences.

c) Develop and optimize a prediction tool as discussed above.

d) The results of this project shall be the property of the federal government. However, the results shall be unrestricted allowing publication at scientific conferences and journals by the vendor.

e) Period of Performance: Start Date: Upon contract award

End Date: NLT 30 Sep 2020

4. Possible Approaches: These are approaches are not mandatory, however, they are provided so that the vendor may benefit from the meteorological expertise of 45 WS on this topic.

A large period of record will be needed to capture enough of these rare events for study.

Use the observations data using Earth Networks total lightning data (both lightning aloft and cloud-to-ground lightning) may be superior to using cloud-to-ground lightning from NLDN for this project.

Since these thunderstorms tend to be weaker with lower flash rate so using total lightning may increase the detection of these storms—they are more likely to produce no cloud-to-ground flashes, especially over the ocean, and so would be more likely to be missed by NLDN.

In addition, if 30% of lightning is cloud-to-ground, then the 22 years of NLDN that would be used

(1996-2018) would be equivalent to about 6 years of ENTLN. But we would have 9 years of ENTLN data (2010-2018).

NLDN detection efficiency performance became fairly stable in east central Florida in 1995, so we often use 1996 and onward NLDN to ensure reasonably consistent detection. Similarly, ENTLN became more reliable in our area for 2010 onward.

Duplicate the area of study used by Embry-Riddle Aeronautical University.

Use the evening RAOB for atmospheric stability information (23 UTC in the lightning season, 00 UTC at other times).

5. This is not a Research Grant or Student Stipend.

6. Deliverables:

1) Report documenting the work, including procedures used to generate those results.

2) Briefing to 45 WS and KSC Weather Office summarizing the work. The vendor shall travel to CCAFS to make the presentation or a telephonic briefing may be acceptable if 45 WS concurs.

7. Pont of Contact: William Roeder, Meteorologist, 45th Weather Squadron, william.roeder@us.af.mil, (321) 853-8410.

8. References:

Cantrell, C. E., 1999: Predicting warm season nocturnal cloud-to-ground lightning near Cape

Canaveral, Florida, M.S. Thesis, Florida State University, Jul 99, 71 pp.

Kelly M., J. Lanicci, W. P. Roeder, 2010: A preliminary investigation of nocturnally forming thunderstorms in the KSC/CCAFS area, Project Report, 29 Apr 2010, 26 pp.

Mazzatti, T. O., and H. E. Fuelberg, 2017: An analysis of total lightning flash rates over Florida, Journal of Geophysical Research, Vol 122, Issue 23, 13 Nov 17, https://doi.org/10.1002/2017JD027579, 12,812-12,826.

mailto:william.roeder@us.af.mil https://doi.org/10.1002/2017JD027579