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Friday, July 25, 2014

Tornado Confirmed in Virginia

 

Tornado Warning Issued at 8:20 AM

The Valid Time Event Code page is a great resource to look back at past warnings issued by each National Weather Service office. The warning was issued 13 minutes prior to the time the damage was reported by the Storm Prediction Center. According to NOAA this 13 minute warning is directly in-line with the average warning time for a tornado. Here's how to make sure you get a weather warning no matter where you are.

Wednesday, July 23, 2014

Watch out for Rip Currents - On Lake Michigan

CourtesyNOAA

Beach Hazards Statement for the Great Lakes

Always hearing about rip currents risk with passing tropical storms or when those long period swells line up just perfectly from a passing storm. The same weather setup can also set up over the great lakes providing some great wave action, but it also poses a risk. The National Weather Service has a whole page dedicated to Great Lakes Hazards including rip currents.

Tuesday, July 22, 2014

The Dragon Bridge looks Amazing




Typhoon Matmo makes Landfall Here

Image source: http://www.kuriositas.com

It is called the Dragon Bridge to the Platform of the Three Immortals and you can read more about it here. It looks amazing, the only problem was I found it by looking for what is around the landfall of Typhoon Matmo. It is ironic the only reason I looked into this was by tracking a typhoon. That very typhoon is now lashing this exact spot.


Typhoon Matmo Approaches Taiwan


Courtesy Central Weather Bureau Taiwan

Friday, July 18, 2014

Wind Direction can Make or Break a Beach Day

Down the Shore Watch the Wind Direction

Growing up in Stone Harbor, NJ I loved those west wind (offshore) days since it made for great waves. I could deal with the colder water and since I was in the water or off the beach, the flies didn't bother me. Times have changed now and anytime I am asked about beach weather I always check the wind first, then the chance for sun or rain.

 

West Wind is Not Good


  • Quickly drops the water temperature due to upwelling
  • Prevents sea breeze so it gets hot
  • Brings in the flies from the marshes and mainland

What to Look for on a Weather Map

Courtesy NOAA
A cold front normally means a drop in temperatures, but plan for the opposite at the beach. This was from last week as a large storm over Eastern Canada brought a series of fronts through the Mid-Atlantic. Normally behind the front the wind will be out of the west or northwest. This blows off shore in NJ.

Courtesy NOAA

Once the front passed and the wind direction changed the water temperature dropped quickly. So when you see a cold front (blue with triangles) then most likely expect a colder ocean to follow. In this case a day after the front passed the water temperature was stuck in the 50s.

Little or no Sea Breeze

You want the sea breeze to develop to enjoy you day on the beach. Often the temperature drops in the afternoon thanks to an onshore wind. Plus the flies from the back bays and mainland will stay there as the wind is blowing onshore. When there is a west wind the sea breeze can't develop so it will really start to heat up and you will be attacked by black flies, greenheads, and mosquitoes. This is a great article on the sea breeze in New Jersey.
 

Don't trust your Phone's Temperature Reading


This has gotten a lot better in recent years only due to more data available and better programs pulling that data but you still can't be sure. The official observation site for Atlantic City, NJ is at the airport well inland and that may be what some programs look for when you enter your location. The temperature difference could be 10 to 20 degrees if a sea breeze develops between there and the beach. If you see a west wind then it is probably about the same but you may find it much cooler than what your readings say depending on where the sensor is located.

What to look for:


  • Watch for an approaching cold front, that might indicate a wind direction change
  • West to northwest winds prevent the sea breeze
    • Warmer air temperature
    • Colder water temperature
    • Flies Everywhere
  • Don't trust your phone. Sometimes the air temperature will be much cooler right at the beach then a block or two away

Thursday, July 17, 2014

Visible Satellite Shows the Smoke

Still my Favorite Analysis Tool

As my Synoptic Meteorology Professor Dr. Ken Crawford would say, "There is a lot of Meteorology happening there." Seems like that can always be said every time you look at a 1km visible satellite image. Put it into motion and then you have something truly amazing.

Here you go, I won't add any loops so no need to lock the door or dim the lights.

GOES West

Stands for Geostationary Operational Earth Satellite and has 2 satellites west and east. Best I found was from Here. Great menu and offers a low and hi res version. This was from July 17th and shows the western US.
GOES West Full Disk
Provided courtesy of University of Wisconsin-Madison\
 Space Science and Engineering Center

 

1km Visible Images of the Current Washington State Wildfire

Washington State Visible
Got this from the NWS in Pendleton, OR
The National Weather Service has some great tools to get close up views of any area. This image was from the Pendleton, OR office. These closeup views you can really see what is happening with the weather that day. This shows the smoke from the fire complexes in Washington State along with the low clouds due to the on shore flow in Western Washington.

This Visible Satellite has some limitations:

  • Only can be used during daylight hours
  • May not distinguish between low and high clouds (Both look white)
  • Clouds and snow can look the same
But at least you can look at the earth in higher resolutions with the visible satellite and that makes it not only nice to look at but you can detect many more atmospheric processes that a low resolution would miss.

Lots of Meteorology Happening Here

Great Visible Picture of the Fires
Photo Courtesy NEXLAB-College of Dupage
 After my first job at KPAX in Missoula, MT I learned real fast how to cover wildfires. After my first Air Quality Alert in the Valley (2000 Wildfires) I saw the value of the Visible satellite image. The image shows the smoke coming from the fires in Central Washington. You can also detect the low clouds from the Pacific moving inland and remaining in the valleys.

From just this image you can determine:
  • Areas affected by the smoke
  • Inversions keeping the low clouds and the smoke trapped in the valleys.
  • An estimate of the wind direction (Northwest)
If you were to animate the image you would be able to see how the smoke was spreading. Plus from the morning to the afternoon you would be able to see if the inversion was breaking or not.

A Look from Below

Washington Department of Transportation

Smoke has lifted just a bit but you can see the extent of the smoke in this traffic camera which is in Western Washington.


Another Great Resource is NASA

NASA Earth Observatory
Courtesy NASA

 One site that always deserves a daily visit is  NASA Earth Observatory. It is not just a satellite gallery but also contains many other graphics that result from NASA research. Along with the image they will often highlight certain features and offer an explanation on the impact of the event.

Tuesday, July 15, 2014

Typhoon Rammasun Strengthens Rapidly

Rapid Intensification Prior to Landfall

Rammasun went from a Tropical Storm with 60 mph wind to a Typhoon with 125 mph wind in just 36 hours. The storm made landfall in the Central Philippines Tuesday. The satellite loop shows a clear eye develop around a solid area of thunderstorms just before the storm impacts land.

Warm Water with little Wind Shear 

Stremlines and contours is what it may look like but this is a map that charts wind shear. The change of wind direction or speed with height can actually rip apart tropical storms. With very low shear and warm water a storm will not be held back from Intensifying.

Highlighted area shows an area with low wind shear. This is the area that Rammasun moved through just prior to landfall in the Philippines.
Water temperatures were just over 85 degrees near the Central Phillipines. This combined with the lack of wind shear led to rapid intensification in the period just prior to landfall.

Just Like Hurricane Humberto

Had to look through a few years of data but remembering where it happened made it a lot easier. Hurricane Humberto went through a similar intensification prior to making landfall in Texas back in 2007.
Date: 12-14 SEP 2007
Hurricane-1 HUMBERTO
ADV  LAT    LON      TIME     WIND  PR  STAT
  1  28.10  -95.20 09/12/15Z   30  1006 TROPICAL DEPRESSION
 1A  28.30  -95.10 09/12/18Z   40  1005 TROPICAL STORM
  2  28.60  -94.90 09/12/21Z   45   999 TROPICAL STORM
 2A  28.80  -94.80 09/13/00Z   45   998 TROPICAL STORM
  3  29.00  -94.60 09/13/03Z   55   995 TROPICAL STORM
  4  29.40  -94.40 09/13/05Z   70   992 HURRICANE-1
  5  29.90  -94.10 09/13/09Z   75   986 HURRICANE-1
The data from the National Hurricane Center shows that the storm went from a depression to a Hurricane in under 24 hours.

Hurricane Humberto Radar just after Landfall




What Does this mean for the Philippines?

 The Philippines Government had already ordered evacuations for many coastal areas and issued alerts in the capitol of Manila for typhoon force winds. The storm should lose some intensity over land but is forecast to increase in strength before impacting Vietnam and China this weekend. The storm can easily be tracked from many agencies.

Monday, July 14, 2014

Severe Storms from Risk to Warning

Severe Weather Outlooks and Advisories

Storm Prediction Center Outlook Map
Convective Outlook from the SPC
The Storm Prediction Center had a larger area under a Slight Risk this morning (July 14, 2014). If your ever concerned about the severe weather then this is the place to start to get a general idea of the risk if any exists.
  • Individual 1,2, and 3 day outlook
  • Day 4-8 outlook
  • Gives threat type on the first day

 

Mesoscale Discussion

Mesoscale Discussion Page from the SPC
The Mesoscale Discussion is released for an area where severe weather conditions begin to develop. It may or may not be followed by a watch. Unlike the outlooks that are always issued days in advance, these discussions are issued as needed. The timeframe for the severe weather developing is usually only a few hours after the discussion is issued. They are not limited to summer severe storms and are often issued when during winter weather events. In this case they will focus on a smaller area of a large scale storm.

 

Severe Watches

Thunderstorm Watch from the SPC
When the conditions look favorable for severe weather then a watch is issued for a particular area. The watch will be issued about 12 to 24 hours before the event is forecast to occur and will remain in effect for the duration. You should expect severe weather in and around the watch area while it is in effect but it may not occur everywhere in the watch area. 

Warnings are Issued by the Local NWS Office

The Storm Prediction Center is located in Norman, OK and issues the outlooks, mesoscale discussions, and watches. Warnings are covered by the individual offices throughout the country. The Philadelphia National Weather Service Office is in the watch area and would put warnings out for the individual storms. A warning is issued when severe weather is happening and will last only during the length of the severe storm.

So are you at risk of severe weather?

  • Check the Storm Prediction Center Outlooks days in advance
    • This will give you an idea of the severe weather threat
  • If your in an area expected to get severe weather check for Mesoscale Discussions that day
    • These are scientific but you may get the idea of how big threat is
  • Keep an eye out for Weather Watches
    • Remember severe weather can happen in and around the watch area
  • If your local office issues a warning then take cover until the warning expires

It's Still the Weather

Severe storms can still happen when there was no risk indicated or watch issued. Often the outlooks are issued for large scale events, a single storm can become severe and not have a warning issued until the severe conditions are reported by a spotter. Always be aware of changing weather even it it looks like no threat exists.

Tuesday, July 8, 2014

Tracking Typhoons

From Hurricane Arthur to Typhoon Neoguri

It may not be as smooth as the National Hurricane Center but you can still track Typhoon Neoguri. The track looks similar and aside from a few added geometric shapes, is the exact same track you would find coming from the NHC.
  • Track Line
  • Center Position Forecast
  • Position estimate circle drawm at each time

Neoguri Track
Japan Meteorological Agency Neoguri Track

 

 Cone of Uncertainty

The forecast issued by any agency is a position estimate for the center of the storm at a given time interval. The storm center at that time has a 67% (70% with the Japan Forecast) of falling within the circle. A line is drawn connecting all the circles and you end up with a forecast cone.

NHC Arthur Cone of Uncertainty
National Hurricane Center Arthur Track
  • Forecast Cone Width Depends on Forecast Uncertainty
  • Cone Appears to Grow Over Time Due to Greater Uncertainty
  • Center of the Storm can Track Anywhere in the Cone

 

Ignore the Forecast Track Line

The NHC does not draw the center line on the forecast track page to avoid misleading the public into a false sense of security should they see the line not crossing their area. The forecast from Arther is a perfect example Above. The center track line would have remained off the coast but the western edge of the cone covered the actual track of the storm. As stated by the Hurricane Center it is important to remember that hazardous conditions could exist outside the cone since it is only represents the center of the storm and not the size.

JTWC

The Joint Typhoon Warning Center (JTWC) is a task force that covers the Pacific and the Indian Ocean. The forecast graphic is not a position probability estimate but a single track with the circles representing the wind speed field.

Joint Typhoon Warning Center Neoguri Track

 

Japan Meteorological Agency

Navigating this page is a little tricky and there are a number of menu options but the track issued is very similar to the National Hurricane Center in the US. The only difference is the probability circles remain on the map which can make it look very geometric. If you look at the center line (then ignore it as stated) you can see each circle with the cone drawn along the outside.

Japan Meteorological Agency Neoguri Track
Japan Meteorological Agency Neoguri Track