Archive for June, 2010

Alex Wednesday
June 30, 2010

Alex is approaching the northeast Mexican coast. The storm is rated category one with winds of 85 mph. It may strengthen before reaching the coast Wednesday night.

NASA GOES Image, Wednesday afternoon, June 30

The satellite image posted above falls in the category of interesting. The circulation of Alex is clearly evident in the western Gulf of Mexico as is a large low pressure system in eastern Canada. A band of clouds “connects” the systems and is the boundary between high pressure reaching from central Canada into the Plains states and more tropical air over the southeast US, the Gulf of Mexico and a large portion of the western Atlantic Ocean. The high pressure over the central US is the main reason that Alex is moving in a primarily westerly direction toward Mexico. The storm is sufficiently large that tropical storm force winds could reach into southern Texas.

John Collins

Alex On Tuesday
June 29, 2010

NASA Image of Tropical Storm Alex Tuesday Afternoon

Alex continues to strengthen winds Tuesday afternoon winds of 70 mph, just below hurricane strength.

The National Hurricane Center forecast track map indicates that Alex is expected to reach hurricane strength as it takes aim at the coast of northeast Mexico and and southeast Texas.

Landfall is expected Thursday morning.

John Collins

Near Record Heat
June 27, 2010

Hazy, Hot & Humid conditions have dominated the first week of summer. Relief should kick in by Tuesday and Wednesday. Until then, records are threatened.

The record highs stack up as follows:

  • 99 … Sunday(June 27)
  • 98 … Monday(June 28)
  • 105 … Tuesday(June 29) (all-time highest temperature recorded in June)

Sunday should be the hottest day and the most likely day that a record would be tied or broken. (UPDATE: at 3:47pm Sunday the temperature hit 100 degrees…a new record for the date and the second time this month that 100 degrees has been reached). Temperatures on Monday will likely back off a few degrees due to scattered clouds and rain chances increasing in the afternoon. A cold front is expected to have passed across the area by Tuesday and temperatures will drop a few more degrees. By Wednesday, afternoon high temperatures are expected to be in the mid-upper 80s, typical for this time of year.

Humidity levels are high as well and heat index values will make the readings “feel like” 100 or a bit higher.

By the way, the approaching cold front on Monday may generate some severe thunderstorm activity. The area needs rain. At BWI-Marshall, precipitation for June is short by 2.03 inches.The Storm Prediction Center has identified much of the area around and east of the Chesapeake Bay Maryland as standing a slight risk for receiving severe weather activity.

John Collins

Less Heat and Humidity … For A While
June 17, 2010

High pressure is moving into the region from the northwest, driving humidity levels down for the time being.

The map above shows the expected weather for Friday evening. The high pressure center will have shifted to the east, over the Atlantic by that time but the area will still be under its’ influence and relatively confortable conditions will prevail.

Warmer, more humid air west of high will begin to filter into the area Saturday and discomfort levels will rise.

The graph above shows the outlook for air temperature (red) and dewpoint temperature (green) for the next seven days. Both lines break into what is considered hot and humid conditions by the weekend. Dewpoint readings in the low 60s and higher indicate a condiderable amount of moisture in the atmosphere. This, combined with high temperatures, results in muggy weather conditions, much like the tropics.

Despite all of this moisture in the air, the rain outlook is somewhat spotty for the next few day. Because of the hit-and-miss nature of rainfall over the past couple of weeks, conditions are on the dry side as far as the garden is concerned. The rain gauge at BWI-Marshall has recorded only 1.04 inches of rain so far in June, .81 inches below the 30 year average. Many areas have received less. The heat expected over the next week will be stressing plant life so make sure the garden gets some water, especially plants in containers.

Just remember, in February summer seemed but a distant dream. Well, summer officially arrives on Monday at 7:28am. Typically the high temperature On June 21 is 84 and the low is 62. Based on the forecast, temperatures should be a little above the seasonal average for the first day of summer.

John Collins

Stormy Wednesday Possible
June 16, 2010

EVENING UPDATE … June 16

By late afternoon the warm front shown below had still not pushed east of the Bay and the cold front was just moving into West Virginia. The combination of a relatively thick cloud deck and southeast winds held temperatures in the 70s (BWI high temperature 79). Rain showers produced only .05 inches of rain at BWI and .46 inches at the Maryland Science Center as of 5:00pm. While severe storms can’t be ruled out, it will be tough for the atmosphere to be destabilized enough to sustain a significant outbreak as the cold front approaches, especially after sunset. Thunderstorm activity could still produce some strong wind gusts, lightening and locally heavy downpours until the front moves east of the area.

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A cold front is approaching the area and some stormy, maybe severe, weather is possible.

Scattered showers in the morning and mid day have been associated with the passage of the warm front noted on the map above. As the cold front approaches during the afternoon and evening a more volatile atmosphere will allow for an increased threat of storms generating damaging winds with smaller threat for hail and tornadoes.

Track storms in your neighborhood with our Interactive Radar on wbaltv.com and check for updates on WBAL-TV 11.

John Collins

First Tropical Cyclone?
June 14, 2010

The first tropical cyclone of the season in the Atlantic Basin may be developing.

A large low pressure area 1,400 miles east-southeast of the Windward Islands of the Caribbean continues to show signs of development. Hurricane forecasters give the system better than even odds that the storm will strengthen to a tropical cyclone. If the storm reaches tropical storm status, its’ name would be Alex.

John Collins

Headed for the Comfort Zone
June 7, 2010

After a week of warm, humid, summer-like conditions, the Mid Atlantic area will be cooling off for a few days. The official thermometer at BWI-Marshall Airport only hit 90 degrees or warmer twice this past week but the excessive humidity made it seem like more.

Relief is being ushered in by a cold front.

The graph above shows the dip in temperatures expected for a few days this week, the result of the passage of a cold front on Sunday. Humidity levels will drop as well as the passing front pushes the tropical air to the south. By the end of the week the tropical heat and humidity are expected to return.

Keep in mind that summer officially starts on Monday, June 21 at 7:28am.

John Collins