1. Regional-scale analysis of convective systems in the 2006 West African Monsoon season Nick Guy Steven Rutledge, Rob Cifelli, and Timothy Lang Colorado State University Tom Rickenbach East Carolina University 21 July 2009

2. Motivations Categorize MCS- and sub-MCS -scale convective systems in 2006 monsoon season Obtain statistics for MCS- and sub-MCS -designated convection on a regional scale Use of multiple platforms for analysis and verification of mesoscale model simulations

3. Radar Locations TOGA NPOL MIT Common Operating Period: 15 August – 16 September 2006 Seasonal Stats #Mean Time (hrs)Total Rain Fraction Total Area Fraction TOGAMCS610.80.6700.395 MaritimeSub-MCS286.50.330.605 NPOLMCS129.50.7330.576 CoastalSub-MCS455.90.2670.424 MITMCS3712.10.9230.873 ContinentalSub-MCS825.20.0770.127

4. Precipitation Climatology Anomaly – Deviation from TRMM climatological precipitation mean WAM Region

5. TOGA (Maritime) [Mean ~ 1.0] NPOL (Coastal) [Mean ~ 0.9] MIT (Continental) [Mean ~ 1.1] Precipitation Precipitation Anomaly

6. Seasonal Rainrates Good trend agreement between ground and satellite products Track bands of precip associated with disturbances 1 2

7. Lightning Climatology NPOL

8. MCS and Sub-MCS Statistics System Stats Mean Conv Fraction Mean CAPE (Jkg -1 ) WWLLN #RainAreaBefore Arrival DuringFlashes (CG) TOGA MCS 60.6140.14911151006107 Maritime Sub-MCS 280.6130.1266586541 NPOL MCS 120.6880.1871630129998 Coastal Sub-MCS 450.7590.2381665152814 MIT MCS 370.6340.1992276162575 Continental Sub-MCS 820.6760.253203722213

9. Case Statistics MCS Case Stats Mean Conv Fraction Mean CAPE (Jkg -1 ) WWLLNT b < 233 K RainAreaBefore Arrival DuringFlashes (CG) Fraction TOGA Case 10.7940.140169715443850.281 Maritime Case 20.7430.2381585779100.175 NPOL Case 10.7100.1872712198910.299 Coastal Case 20.6050.17316169291500.555 MIT Case 10.5320.11024469032200.356 Continental Case 20.7360.24823822344110.320

10. Vertical Structure

11. Summary 2006 WAM season is “average” –Via TRMM rainfall and lightning climatology (domain: 0-30N, 30W-30E) Regional analysis defined via 3 radar sites represents continental, coastal, and maritime locations –TOGA (maritime) domain average for precipitation –NPOL (coastal) domain below average for precipitation –MIT (continental) domain slightly above average for precipitation –MCS scale events constitute greater fraction of rainfall inland Large precipitation events tracked across longitudinal domain No apparent first order correlation to environmental variables – must look at wave forcing as well Vertical structure varies with region, resembling typical “continental” and “maritime” structures

12. Future Work AEWs: Define and calculate associated convective statistics for each domain Case Studies: –5-10 Sep 2006 possibly associated with non- developing wave –8-12 Sep 2006 possibly associated/interacts with wave that produced Hurricane Helene –12-14 Sep 2006 Closer look at the satellite vs. ground products relationship Work with NASA Goddard Space Flight Center (Greenbelt, MD) to assess mesoscale model simulations of 2006 WAM events

13. Wave Passages Wave definitions from Janicot et al (2008)