Transcript NHC Training ppt

Geostationary Lightning Mapper (GLM)
GLM detects total strikes: in cloud, cloud to cloud, and cloud to ground
• Near uniform spatial
resolution of approximately
10 km.
• Coverage up to 52 deg
latitude.
• 70-90% flash detection day
and night over the Americas
and adjacent ocean regions.
• < 20 sec product latency
• Provides additional
information about TC
intensity changes and of
severe weather events.
LIS/OTD Combined Lightning 1997-2005
1
2011 NHC Proving Ground Products
Rapid Intensification Index (RII)
Mark DeMaria / John Knaff
2
Lightning-Based Tropical Cyclone
Rapid Intensification Index (RII)
• Ground-based lightning data used as a proxy for
GOES-R GLM
• NHC real-time rapid intensification index (RII)
– Input from GFS model, GOES imagery, oceanic heat
content analyses, Reynolds SST, persistence
– Discriminant analysis provides probability of max wind
increase of at least 30 kt in 24 hr
• Experimental version adds lightning density input
– 6 hr storm-relative composites
– 2005-2010 developmental sample from WWLLN
– Real time in 2011 from WWLLN feed at CIRA
• Last year Vaisala used in real time, which introduced additional
source of error
– Text product distributed from CIRA
– Analogous to text product for operational RII
3
6 hour WWLLN Lightning Strikes -- Hurricane Omar 16 Oct 2008
RII predictors include inner core (0-100 km) and
rainband (200-300 km) lightning strike density
4
Sample Text Output from
2010 product
Lightning-Based Rapid
Intensification Forecast Algorithm
Hurricane Alex
30 June 2010 00 UTC
Will be available at: ftp://rammftp.cira.colostate.edu/demaria/NHCPG
5
Summary of 2011 RII Changes
• WWLLN used in real time, consistent with
developmental sample
• Output will also include rapid weakening
probability
– Max wind decrease of 20 kt or more in 24 hr
– Valid for storms over water