Tropical Disturbances

Shown below are longitude-time plots of 850 and 200 hPa meridional winds at 15N in MRF analyses and forecasts for the Pacific and the Atlantic. They display westward-propagating disturbances. Time series of longer range forecasts tend not to show propagating disturbances, although individual forecasts do display propagation out to 15 days.

Atlantic (120W-0)

15N

850 hPa

1 day fcsts	3 day fcsts	5 day fcsts	7 day fcsts	8 day fcsts	10 day fcsts	15 day fcsts
Verifying analyses	Verifying analyses	Verifying analyses	Verifying analyses	Verifying analyses	Verifying analyses	Verifying analyses
Error	Error	Error	Error	Error	Error	Error

15 day fcst from Aug. 7

Verifying Analyses

200 hPa

1 day fcsts	3 day fcsts	5 day fcsts	7 day fcsts	8 day fcsts	10 day fcsts	15 day fcsts
Verifying analyses	Verifying analyses	Verifying analyses	Verifying analyses	Verifying analyses	Verifying analyses	Verifying analyses
Error	Error	Error	Error	Error	Error	Error

15 day fcst from Aug. 7

Verifying Analyses

TOA OLR (compare to verifying analyses for 1 day fcsts)

Equator

850 hPa

1 day fcsts	3 day fcsts	5 day fcsts	7 day fcsts	8 day fcsts	10 day fcsts	15 day fcsts
Verifying analyses	Verifying analyses	Verifying analyses	Verifying analyses	Verifying analyses	Verifying analyses	Verifying analyses
Error	Error	Error	Error	Error	Error	Error

TOA OLR (compare to verifying analyses for 1 day fcsts)

Pacific (90E-90W)

850 hPa

15N

1 day fcsts	3 day fcsts	5 day fcsts	7 day fcsts	8 day fcsts	10 day fcsts	15 day fcsts
Verifying analyses	Verifying analyses	Verifying analyses	Verifying analyses	Verifying analyses	Verifying analyses	Verifying analyses
Error	Error	Error	Error	Error	Error	Error

TOA OLR (compare to verifying analyses for 1 day fcsts)

15 day fcst from Aug. 7

Verifying Analyses

Equator

1 day fcsts	3 day fcsts	5 day fcsts	7 day fcsts	8 day fcsts	10 day fcsts	15 day fcsts
Verifying analyses	Verifying analyses	Verifying analyses	Verifying analyses	Verifying analyses	Verifying analyses	Verifying analyses
Error	Error	Error	Error	Error	Error	Error

TOA OLR (compare to verifying analyses for 1 day fcsts)