U.S. had most extreme spring on record for precipitation

By: Dr. Jeff Masters , 2:20 PM GMT on June 14, 2011

Nature's fury reached new extremes in the U.S. during the spring of 2011, as a punishing series of billion-dollar disasters brought the greatest flood in recorded history to the Lower Mississippi River, an astonishingly deadly tornado season, the worst drought in Texas history, and the worst fire season in recorded history. There's never been a spring this extreme for combined wet and dry extremes in the U.S. since record keeping began over a century ago, statistics released last week by the National Climatic Data Center (NCDC) reveal. Their Climate Extremes Index (CEI) looks at the percentage area of the contiguous U.S. experiencing top 10% or bottom 10% monthly maximum and minimum temperatures, monthly drought, and daily precipitation. During the spring period of March, April, and May 2011, 46% of the nation had abnormally (top 10%) wet or dry conditions--the greatest such area during the 102-year period of record. On average, just 21% of the country has exceptionally wet conditions or exceptionally dry conditions during spring. In addition, heavy 1-day precipitation events--the kind that cause the worst flooding--were also at an all-time high in the spring of 2011. However, temperatures during spring 2011 were not as extreme as in several previous springs over the past 102 years, so spring 2011 ranked as the 5th most extreme spring in the past 102 years when factoring in both temperature and precipitation.


Figure 1. Nine states in the U.S. saw their heaviest precipitation in the 117-year record during spring 2011, with record-breaking precipitation concentrated in the Pacific Northwest and along the Ohio River. Seven other states had top-ten wettest springs. Texas had its driest spring on record, and New Mexico and Louisiana had top-ten driest springs. When compared with Figure 2, we see that this is a classic winter La Niña pattern, but at extreme amplitude. Image credit: NOAA/NCDC.


Figure 2. La Niña events since 1950 have brought wetter than average conditions to the Pacific Northwest and Ohio River Valley in winter, and drier than average conditions to the South in both winter and spring. Spring 2011 (Figure 1) had a pattern very similar to the classic winter La Niña pattern (left image in Figure 2.) Image credit: NOAA Climate Prediction Center.


Figure 3. The percent area of the Contiguous U.S. experiencing much above average heavy 1-day precipitation events in spring 2011 hit a record high, nearly 16%. The 102-year average is 9%. The previous record of 15.5% was set in 1964. Heavy springtime 1-day precipitation events in the U.S. have been increasing since 1960, in line with measured increases in water vapor over the U.S. due to a warming climate. See also Figure 4 below. Image credit: NOAA/NCDC.


Figure 4. Percent increase in the amount falling in heavy precipitation events (defined as the heaviest 1% of all daily events) from 1958 to 2007, for each region of the U.S. There are clear trends toward more very heavy precipitation events for the nation as a whole, and particularly in the Northeast and Midwest. Climate models predict that precipitation will increasingly fall in very heavy events, similar to the trend that has been observed over the past 50 years in the U.S. Image credit: United States Global Change Research Program. Figure updated from Groisman, P.Ya., R.W. Knight, T.R. Karl, D.R. Easterling, B. Sun, and J.H. Lawrimore, 2004: Contemporary changes of the hydro-logical cycle over the contiguous United States, trends derived from in situ observations. Journal of Hydrometeorology, 5(1), 64-85.

What caused this spring's extremes?
During a La Niña episode in the Eastern Pacific, when the equatorial waters cool to several degrees below average, abnormally dry winter weather usually occurs in the southern U.S., and abnormally wet weather in the Midwest. This occurs because La Niña alters the path of the jet stream, making the predominant storm track in winter traverse the Midwest and avoid the South. Cold, Canadian air stays north of the jet stream, and warm subtropical air lies to the south of the jet, bringing drought to the southern tier of states. La Niña's influence on the jet stream and U.S. weather typically fades in springtime, with precipitation patterns returning closer to normal. However, in 2011, the La Niña influence on U.S. weather stayed strong throughout spring. The jet stream remained farther south than usual over the Pacific Northwest and Midwest, and blew more strongly, with wind speeds more typical of winter than spring. The positioning of the jet stream brought a much colder than average spring to the Pacific Northwest, with Washington and Oregon recording top-five coldest springs. Spring was not as cold in the Midwest, because a series of strong storms moved along the jet stream and pulled up warm, moist Gulf of Mexico air, which mixed with the cold air spilling south from Canada. The air flowing north from the Gulf of Mexico was much warmer than usual, because weaker winds than average blew over the Gulf of Mexico during February and March. This reduced the amount of mixing of cold ocean waters from the depths, and allowed the surface waters to heat up. Sea surface temperatures (SSTs) in the Gulf of Mexico warmed to 1°C (1.8°F) above average during April--the third warmest temperatures in over a century of record keeping (SST anomalies were a bit cooler in May, about 0.4°C above average, due to stronger winds over the Gulf.) These unusually warm surface waters allowed much more moisture than usual to evaporate into the air, resulting in unprecedented rains over the Midwest when the warm, moist air swirled into the unusually cold air spilling southwards from Canada. With the jet stream at exceptional winter-like strengths, the stage was also set for massive tornado outbreaks.


Figure 5. A La Niña-like positioning of the jet stream, more typical of winter than spring, brought much colder air than normal to the Pacific Northwest and Upper Midwest during the spring of 2011. Washington and Oregon had top-five coldest springs, and near-record snowfalls and snow packs were recorded in portions of the Northern Rockies and Northern Plains. South of the mean position of the jet stream, top-ten warmest springs were recorded in Texas, New Mexico, and Louisiana. Image credit: NOAA/NCDC.

Was climate change involved?
Whenever an unprecedented series of extreme weather events hit, it is natural to ask how climate change may be affecting the odds of these events, since our climate is undergoing unprecedented changes. This spring's unusual precipitation pattern--wet in the Northern U.S., and dry in the South--does fit what we'd expect from a natural but unusually long-lived winter La Niña pattern (Figure 2). However, it also fits the type of precipitation pattern climate models expect to occur over the U.S. by the end of the century due to human-caused warming of the climate (though shifted a few hundred miles to the south, Figure 6.) This drying of the Southern U.S. and increased precipitation in the Northern U.S. is expected to occur because of a fundamental shift in the large scale circulation of the atmosphere. The jet stream will retreat poleward, and rain-bearing storms that travel along the jet will have more moisture to precipitate out, since more water vapor can evaporate into a warmer atmosphere. The desert regions will expand towards the poles, and the Southern U.S. will experience a climate more like the desert regions of Mexico have now, with sinking air that discourages precipitation. A hotter climate will dry out the soil more, making record intensity droughts like this year's in Texas more probable. So, is it possible that the record extremes of drought and wetness this spring in the U.S. were due to a combination of La Niña and climate change. It is difficult to disentangle the two effects without doing detailed modelling studies, which typically take years complete and publish. One weakness in the climate change influence argument is that climate models predict the jet stream should retreat northwards and weaken due to climate change. Indeed, globally the jet stream retreated 270 miles poleward and weakened during the period 1970 - 2001, in line with climate model expectations. Thus, a stronger and more southerly jet stream over the U.S. during the spring is something we should expect to see less and less of during coming decades.


Figure 6. The future: simulated change in precipitation during winter and spring for the years 2089 - 2099 as predicted by fifteen climate models, assuming we continue high emissions of heat-trapping carbon dioxide. Confidence is highest in the hatched areas. Compare with Figure 7, the observed change in precipitation over the past 50 years. Image credit: United States Global Change Research Program.


Figure 7. U.S. annual average precipitation has increased by about 5% over the past 50 years, but there has been pronounced drying over the Southeast and Southwest U.S. Even in these dryer regions, though, heavy precipitation events have increased (see Figure 4.) Thus, rainfall tends to fall in a few very heavy events, and the light and moderate events decrease in number. Image credit: United States Global Change Research Program. Data plotted from http://www.ncdc.noaa.gov/oa/climate/research/ushc n/.

Keep in mind, though, that climate models are best at describing the future global average conditions, and not at predicting how climate change might affect individual continents--or at predicting how rare extreme events might change. Major continent-scale changes in atmospheric circulation are likely to result over the coming few decades due to climate change, and I expect the jet stream will shift farther to the south in certain preferred regions during some combination of seasons and of the natural atmospheric patterns like La Niña, El Niño, and the Arctic Oscillation. For example, there has been research published linking recent record Arctic sea ice loss to atmospheric circulation changes in the Arctic Oscillation that encourage a southwards dip of the jet stream over Eastern North America and Western Europe during late fall and winter. Until we have many more years of data and more research results, we won't be able to say if climate change is likely to bring more springs with a circulation pattern like this year's.

One thing we can say is that since global ocean temperatures have warmed about 0.6°C (1°F) over the past 40 years, there is more moisture in the air to generate record flooding rains. The near-record warm Gulf of Mexico SSTs this April that led to record Ohio Valley rainfalls and the 100-year $5 billion+ flood on the Mississippi River would have been much harder to realize without global warming.

I'll have a new post by Thursday.

Jeff Masters


The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.

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Quoting reedzone:
I'm one of the few that back Governor Rick Scott strongly. He's doing the right thing, but people do not like "the right thing" anymore. He's a born again Christian, and while he only has one term, he can get things done. I'm tired of the bickering from the liberals back and forth on Perry and Scott. They do what GOD wants and not what you all want. It's in GODS will, not ours. Sometimes, we have to lose alot to gain much more. I applaud Rick Scott on the laws he has passed, taking out the trashy teachers and bringing in more better teachers that will teach and not sit around.
.....your clueless,since elected he's cut the budget for the states most vounerable citizens the elderly,disabled and thats not to mention the education cuts and corporate tax brakes he's handed out to all his old buddies,also involved in the states biggest medicaid fraud....gives christians a bad name imo
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Quoting NRAamy:
cool, SQUAWK! Photos on facebook?

:)


Yup. Top hat and tails. Monopoly man.
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OK.
So GOD is going to keep things Good.
But He cannot do it on His own.

God helps those that help themselves.

So it is time to Listen to the Warnings being given, and time to Demand that your Leaders do the Right Thing and deal with OUR influences regarding Climate Change.

GOD is sending Warnings ALL THE TIME recently.

There are none so blind as those who will not see.

Ignorance is Bliss.

etc
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taking out the trashy teachers and bringing in more better teachers that will teach and not sit around.

I ain't gonna touch it... no I ain't...

;)
Member Since: December 31, 1969 Posts: Comments:
Western Hills, Del Rio, Texas (PWS)
Clear
105.9 °F
Clear
Humidity: 26%
Dew Point: 64 °F
Wind: 0.0 mph
Wind Gust: 0.0 mph
Pressure: 29.84 in (Falling)
Heat Index: 110 °F
Visibility: 10.0 miles
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cool, SQUAWK! Photos on facebook?

:)
Member Since: December 31, 1969 Posts: Comments:
Quoting reedzone:
I'm one of the few that back Governor Rick Scott strongly. He's doing the right thing, but people do not like "the right thing" anymore. He's a born again Christian, and while he only has one term, he can get things done. I'm tired of the bickering from the liberals back and forth on Perry and Scott. They do what GOD wants and not what you all want. It's in GODS will, not ours. Sometimes, we have to lose alot to gain much more. I applaud Rick Scott on the laws he has passed, taking out the trashy teachers and bringing in more better teachers that will teach and not sit around.


LMAO!....Reed you make me laugh :)
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Quoting Jax82:
Despite rain yesterday, da forest is still smokin' today. It's currently 99 degrees.






96 today in Jupiter. We don't see that too often this close to the beach. A lot better than the sub-zero winter temps I grew up in though.
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NE Florida is always burning seems like
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Quoting NRAamy:
after 22 days, if the water is gone, what will people do?


Keep going to the SFWMD's water supply is the best option.
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Quoting NRAamy:
after 22 days, if the water is gone, what will people do?


I don't know truthfully and I don't know if they do either? I personally don't think it will come to that as the long awaited rains have started.
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atmo.... breathe deeply....

;)
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Quoting NRAamy:
after 22 days, if the water is gone, what will people do?


RIOT, PROTEST, KILL
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*sigh*
Bad to worse. To whomever started with the political figures, thanks.
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after 22 days, if the water is gone, what will people do?
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Quoting reedzone:
I'm one of the few that back Governor Rick Scott strongly. He's doing the right thing, but people do not like "the right thing" anymore. He's a born again Christian, and while he only has one term, he can get things done. I'm tired of the bickering from the liberals back and forth on Perry and Scott. They do what GOD wants and not what you all want. It's in GODS will, not ours. Sometimes, we have to lose alot to gain much more. I applaud Rick Scott on the laws he has passed, taking out the trashy teachers and bringing in more better teachers that will teach and not sit around.


In case if you haven't heard, politics and religion DO NOT MIX. I feel a s***storm comin' from this post....

Haven't you seen what he plans to do with the state? I mean c'mon. Cutting teachers, public workers. What good does that do? Nothing. Like cmahan said, if it's God's will, then this state is going to be a living hell in a couple years.
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Quoting reedzone:
I'm one of the few that back Governor Rick Scott strongly. He's doing the right thing, but people do not like "the right thing" anymore. He's a born again Christian, and while he only has one term, he can get things done. I'm tired of the bickering from the liberals back and forth on Perry and Scott. They do what GOD wants and not what you all want. It's in GODS will, not ours. Sometimes, we have to lose alot to gain much more. I applaud Rick Scott on the laws he has passed, taking out the trashy teachers and bringing in more better teachers that will teach and not sit around.


You won't attract good teachers by cutting the pay another 3%
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Quoting NRAamy:
Did you hear WPB has only 3 weeks worth of water left and is secretly buying water from SFWMD?

What?? Say true?



I heard 22 days left.

Rain chances bumped up to 50% and to be focused in Palm Beach County this afternoon.

SHORT TERM FORECAST WAS UPDATED FOR THE CHANCE OF SHOWERS AND
THUNDERSTORMS THIS AFTERNOON AND EARLY EVENING. THE CURRENT RUNS
OF THE LOCAL MESOSCALE MODELS INDICATE THAT CONVECTION IS POSSIBLE IN
THE AFTERNOON AND EVENING...MAINLY FOCUSED ACROSS THE NORTHEASTERN
PART OF THE CWA BUT ALSO POSSIBLE ACROSS MOST OF THE EASTERN
PENINSULA. THERE IS CURRENTLY A WEAK FRONT ACROSS CENTRAL FLORIDA
THAT IS FORECAST TO APPROACH SOUTH FLORIDA IN THE EVENING. IN
ADDITION THE CURRENT MESOSCALE MODEL RUNS SUGGEST THAT A WEAK EAST
COAST SEA BREEZE WILL FORM LATER IN THE AFTERNOON...THERE SHOULD
BE A DELAY DUE TO THE WEAK WESTERLY FLOW ACROSS THE REGION.
THE
12Z SOUNDING INDICATED ENHANCED LAPSE RATES JUST BELOW THE MID
LEVELS AND WITH THE WESTERLY FLOW HIGHER TEMPERATURES CAN BE
EXPECTED ALONG THE EASTERN PORTIONS OF THE PENINSULA. GIVEN ALL
THESE FACTORS...SCATTERED SHOWERS AND THUNDERSTORMS POSSIBLE
ACROSS MAINLY THE EASTERN HALF OF THE PENINSULA AND MORE FOCUSED
ACROSS PALM BEACH COUNTY. A FEW STRONG THUNDERSTORMS ARE POSSIBLE
WITH THIS ACTIVITY.
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Quoting padirescu:


Near the Publix on Seminole Pratt.


I got a few friends out that way. But that's cool, nice area.
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Quoting NRAamy:
canes, that's awful.... I had no idea.... I thought you guys got tons of rain there....



Nope, haven't gotten much in months.
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Other day I was watering the foundation of the house and behind some shrubs I looked back there where the mulch is supposed to touch the slab, it was 1 1/2 inches away from it, I poured water coming out of the hose and the water was going down into to blackness and had no idea where it was going, it was dissapearing into oblivion as it poured outta the hose... wasn't even backing up, it was going straight down to hell seemed like
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Quoting FtMyersgal:
#272 Rita Evac that's insane. We had about .20 inch at my house along the Caloosahatchee on Sunday late afternoon. Spotty showers to say the least in the area but welcome rain for our lawn and plants. I'll keep hopeful watch some comes your way very soon. A nice little blurb in the Yucatan might be just the ticket


Insane it is, and thy drought continues
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Quoting caneswatch:


Nice. I'm in RPB. Used to live out in the Acreage for 12 or so years. Are you closer to Persimmon or Northlake?


Near the Publix on Seminole Pratt.
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Ehh, nevermind.
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#272 Rita Evac that's insane. We had about .20 inch at my house along the Caloosahatchee on Sunday late afternoon. Spotty showers to say the least in the area but welcome rain for our lawn and plants. I'll keep hopeful watch some comes your way very soon. A nice little blurb in the Yucatan might be just the ticket
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Quoting padirescu:


Acreage


Nice. I'm in RPB. Used to live out in the Acreage for 12 or so years. Are you closer to Persimmon or Northlake?
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canes, that's awful.... I had no idea.... I thought you guys got tons of rain there....

Member Since: December 31, 1969 Posts: Comments:
Good Afternoon...

Solar forecast hints at a big chill
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Quoting Patrap:
Pieces of Comet Halley Strike the Moon
Posted on May 16, 2011 12:22:45 AM |


Three meteoroids were seen hitting the moon last week -- all of them possible pieces of Comet Halley! The Eta Aquariid -- the meteor shower caused from Comet Halley, see post below -- radiant was positioned so that almost the entire visible part of the moon was exposed to it. On the evenings of May 9-11, members of the Meteoroid Environment Office were out doing lunar observations and a meteoroid impact was seen each night.

The peak of the Eta Aquariids was the morning of May 5, but the rate is still high and meteors associated with this shower were still seen last week in multiple cameras over Alabama and surrounding states.

The following images are stills from the videos recorded those evenings; the impacts are seen on the dark portion of the moon.
....these are the first signs of the invasion,just in. time for hurricane season,i bet we have a tropical threater by months end...
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Quoting caneswatch:



I'm in the western part of the county as well. That storm gave some good rain. Where in western county are you?


Acreage
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Quoting NRAamy:
Did you hear WPB has only 3 weeks worth of water left and is secretly buying water from SFWMD?

What?? Say true?


LOL

Only a few in the city government had any idea that it was happening, and the mayor wasn't one of them.
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Dead or dying CrapeMyrtles seen here, ones on the left are green because of water sprinkler system, but locations that don't have sprinklers... this is the norm

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This just in:

Sun's Fading Spots Signal Big Drop in Solar Activity

The results of the new studies were announced today (June 14) at the annual meeting of the solar physics division of the American Astronomical Society, which is being held this week at New Mexico State University in Las Cruces.

Link

"...Currently, the sun is in the midst of the period designated as Cycle 24 and is ramping up toward the cycle's period of maximum activity. However, the recent findings indicate that the activity in the next 11-year solar cycle, Cycle 25, could be greatly reduced. In fact, some scientists are questioning whether this drop in activity could lead to a second Maunder Minimum, which was a 70-year period from 1645 to 1715 when the sun showed virtually no sunspots..."

If the models prove accurate and the trends continue, the implications could be far-reaching.

"If we are right, this could be the last solar maximum we'll see for a few decades," Hill said. "That would affect everything from space exploration to Earth's climate."

Remember, the LIA (Little Ice Age) occured during the Maunder Minimum.

From Wiki - "...The Maunder Minimum coincided with the middle - and coldest part - of the Little Ice Age, during which Europe and North America were subjected to bitterly cold winters. Whether there is a causal connection between low sunspot activity and cold winters has not been proven; however, lower earth temperatures have been observed during low sunspot activity..."

Time will tell...
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Quoting hurricanejunky:


You mean "to save his life"?


Same thing LOL
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Did you hear WPB has only 3 weeks worth of water left and is secretly buying water from SFWMD?

What?? Say true?
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Quoting Grothar:
Boy, tough crowd today. I think I will go back and stick to just posting images and you all can go draw your own conclusions. Geez!! You won't have old Grothar to kick around anymore. (Now don't anybody tell me that the colors aren't right.)




You forgot your dog

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Quoting padirescu:


Hopefully the trend from yesterday continues. We got a nice 30 minutes of steady rain yesterday afternoon out here in the western part of the county. One heck of a rainbow afterward as well.



I'm in the western part of the county as well. That storm gave some good rain. Where in western county are you?
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Link

Latest water restrictions for West Palm Beach.

Link

West Palm Beach only 15 days of water remaining as of today's update.
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Quoting FtMyersgal:

RitaEvac, what are your rain chances lately? Have you had ANYTHING lately? Geez it's dry here but nothing like what Texas is seeing!


0

about 0.22" for the month over my head.
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Quoting Patrap:
Pieces of Comet Halley Strike the Moon
Posted on May 16, 2011 12:22:45 AM |



The words I keep thinking of to describe this might get me a re-port, so let me try to tone it down: neato!
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Quoting Grothar:


Link, please! I know I saw something on the news late last night, that the water table in Dade-Broward was much lower than had been estimated. I believe our water restrictions may go even tighter soon.

West Palm Beach could run out of water soon.
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Global Tropical Hazards Assessment


Excerpt:

As we move into Week-2, an active Indian monsoon favors a continuation of enhanced rainfall for India and the Bay of Bengal. Forecast model guidance also continues to indicate enhance rainfall near the Philippines. The potential for tropical storm development also remains elevated near the Philippine islands. Model forecast guidance suggests a change across the southern areas of the North American monsoon region and northern Central America during the period to increased chances for above-average rainfall. Further tropical development is possible into Week-2 across the eastern Pacific basin. There is also some threat for potential tropical development in the Bay of Campeche during the period. Model guidance indicates a disturbance moving northward toward the Gulf coast potentially providing beneficial rainfall drought parched areas of the souther U.S.. The potential at the current time for this is low, however.

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Cat 6 lead authors: WU cofounder Dr. Jeff Masters (right), who flew w/NOAA Hurricane Hunters 1986-1990, & WU meteorologist Bob Henson, @bhensonweather

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