A tropical wave (Invest 95L)
that moved off the coast of Africa on Friday was between the Cape Verde Islands
and Africa on Saturday morning, but is headed west-northwest into drier air. Satellite loops
show the wave has a closed surface circulation, but heavy thunderstorm activity is lacking due to high wind shear
of 25 knots and dry air. Water vapor satellite images
and the Saharan Air Layer analysis
show that 95L is entering a dry airmass. Sea Surface Temperatures beneath 95L were a marginal 26°C on Saturday, but were predicted to fall to 25.5°C by Sunday, limiting the potential for development. The wave is drifting slowly west-northwest, and will affect the weather over the Cape Verde Islands
Saturday and Sunday. None of the reliable computer models for predicting tropical storm formation (GFS, European, and UKMET) develop 95L. In their 8 am EDT Saturday Tropical Weather Outlook, NHC gave 94L 2-day and 5-day development odds of 20%.
A second tropical wave midway between the Cape Verdes Islands and the Lesser Antilles Islands is headed west at about 15 mph. This wave has a decent amount of spin, but has very limited heavy thunderstorms due to dry air. Some of the members of the GFS and European ensemble model predict that this wave could develop, but the atmosphere is likely far too dry for this to occur.Figure 1.
MODIS true-color image of 95L between the coast of Africa and the Cape Verde Islands at approximately 8:00 am EDT August 16, 2014. Image credit: NASA.The story of this week's remarkable floods in Detroit, Baltimore, Long Island, and Maine
This week saw one of the most remarkable summer rainstorms in U.S. history, as Detroit, Baltimore, Long Island, and Maine all suffered top-five rainiest days in their history. Wunderground's weather historian, Christopher C. Burt, offers his take on the storm in his latest post, Incredible East Coast Rainfall Event of August 12-14
. Dr. Marshall Shepherd, who is Director of the Atmospheric Sciences Program at University of Georgia and 2013 President of the American Meteorological Society (and hosts a noon EDT Sunday weather talk show on The Weather Channel called "Weather Geeks"), has a post discussing this topic in more detail, Recent Urban Floods: A simple equation
. His equation:
Urban Flooding = Increase in intensity
of top 1% rain events + expanding urban impervious
land cover + storm water management engineered for rainstorms of "last century"Figure 2.
Flooding near Islip, New York, on August 13, 2014. Islip set an all-time New York state record for 24-hour precipitation with 13.57". Image credit: wunderphotographer Hurricane765.
Wunderground has an excellent new infographic on floods.
Wunderground's climate change expert, Dr. Ricky Rood, offers his thoughts on this week's remarkable floods.