I feel very confident that we have safely passed through the first flooding threat. As I said on the air yesterday, the snowpack before this last storm had between .5" to 1.5" worth of water in it. This past storm brought 1" of rain and if we released all of the snowpack, we would have had some problems. The biggest threat for that in the first storm was in the lower elevations south of I-80. The good news was that the snowpack was cold enough and the rain was cold enough for the snow to absorb the rainfall.
Check out this web page to see the temperature of the snow pack when the storm started on Thursday evening. The red areas were primed to melt, while the white and blue areas were still cold below freezing. Those colder areas ended up primed to absorb the rainfall. Which then just adds to the moisture content waiting on the ground. This means that there is 1.5-2.5" of rainfall stored primed to cause flooding with the next warm rainfall on Monday. Which means that we may have delayed instead of dodging.
Though there is some good news. Now check out this web page to see what the snowpack temperatures were at 11am this morning. The snow has warmed. And that means melting will continue, but without rainfall as most of the precipitation is done. This means that the lower elevations south of I-80 will bleed away some of that water at a safe rate today and then again Sunday with temperatures reaching above freezing. The more that we bleed away, the better we will be when a heavy and warm rainfall comes Monday. That system will cause flooding in some areas. It will be inevitable, but the extent is still unknown. The more we lose until then, the better off we will be.
Of course either way, you should keep an eye on river levels if you live near one. We have redesigned our web page. Check it out: http://wearecentralpa.com/riverlevels
Chief Meteorologist Joe Murgo
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