Get Out of the Floodplain…And Get Your Stuff Out Too!

After threading its way through waves of Saharan dust plumes, Tropical Storm Isaias, or the remnants thereof, is making a run up the eastern seaboard toward the lower Susquehanna watershed.

Isaias formed just off the northernmost tip of the South American continent.  It drifted north in a narrow pocket between two waves of the Saharan dust plume and, on July 30, strengthened to tropical storm status while in the vicinity of Puerto Rico.  (CIRA/NOAA image)
In this image taken on Friday, note the position of the fast-moving dust plume that was to the southeast of Isaias just a day earlier.  With the storm now clear of the dry Saharan air, it strengthens to become Hurricane Isaias.  (CIRA/NOAA image)
On Friday, the National Hurricane Center issues advisors expecting the strengthening Isaias to sweep the Atlantic coasts of Florida, Georgia, and South Carolina as a hurricane with winds of 74 miles per hour or greater.  (NOAA/National Hurricane Center image)
Then on Saturday, Isaias appears to be back in the dirt.  Did the counterclockwise rotation of the atmosphere around Isaias draw in Saharan dust and dry air to weaken the storm?  Whatever the cause, Isaias is downgraded to a strong tropical storm with maximum sustained winds of 70 miles per hour.  (CIRA/NOAA image)
The latest image of Tropical Storm Isaias.  (CIRA/NOAA image)
The latest forecast projects Isaias will briefly reach hurricane status later today before making landfall in South Carolina and again weakening.  (NOAA/National Hurricane Center image)
Tropical Storm Isaias is expected to bring heavy rain to the lower Susquehanna valley and the Cheapeake Bay region tomorrow (Tuesday).  (NOAA/National Hurricane Center image)

Heavy rain and flooding appears likely, particularly east of the Susquehanna.  Now might be a good time to clean up the trash and garbage that could clog nearby storm drains or otherwise find its way into your local waterway.  NOW is the time to get all your stuff out of the floodplain!  The car, the camper, the picnic table, the lawn furniture, the kid’s toys, the soda bottles, the gas cans, the lawn chemicals, the Styrofoam, and all that other junk you’ve piled up.  Get that stuff cleaned up and out of the floodway.  And of course, get you and your pets out of the there too!

Tropical Storm Fay

Tropical Storm Fay bringing rain and the possibility of flooding to the lower Susquehanna watershed.  As of 3:30 P.M. E.D.T., the northbound center of circulation was just off Atlantic City, New Jersey.  (CIRA/NOAA image)

2018 Migration Count Summary: Rainout

If you were a regular visitor to this website during the autumn of 2017, you will recall the proliferation of posts detailing the bird migration at Conewago Falls during the season.  The lookout site among the Pothole Rocks remained high and dry for most of the count’s duration. 

In the fall of 2018, those lookout rocks were never to be seen. There was to be no safe perch for a would-be observer. There was no attempt to conduct a tally of passing migrants. If you live in the lower Susquehanna River drainage basin, you know why—rain—record setting rain.

Annual precipitation during 2018 as indicated by radar.  Note the extensive areas in pink.  They received in excess of 70 inches of precipitation during 2018, much of it during the second half of the year.  (NOAA/National Weather Service image)
Average annual rainfall.  Most of the lower Susquehanna drainage basin receives an average of just over 40 inches of rain each year.  (NOAA/National Weather Service image)
Departure from normal annual precipitation totals.  Note the extensive areas of greater than 20 inches of precipitation above normal (pink).  Severe flooding occurred on many streams during numerous events throughout the second half of 2018.  Note the closer to normal totals in central New York in the upper Susquehanna watershed.  The lesser amounts of rain there and the localized pattern of the flooding events in Pennsylvania prevented the main stem of the lower Susquehanna from experiencing catastrophic high water in 2018.  (NOAA/National Weather Service image)   
Though there has been no severe flooding, frequent rain events in the Susquehanna watershed have maintained persistently high river levels in Conewago Falls.  Pothole Rocks seen here on December 9 during an ebb in the flow were soon inundated again as rains fell in the Susquehanna basin upstream. 
Of course, each time the river receded it left behind a fresh pile of plastic garbage.  What didn’t end up on the shoreline found its way to Chesapeake Bay…then on to the Atlantic.  Is that your cooler?