The Forecast Wildcard: NormanSeptember 30th, 2012 at 4:25 pm by Chad Evans under Chad's WLFI Weather Blog
New data has the remnants of Tropical Storm Norman making a sharp turn to the north, then northwest, bringing some showers Monday evening-night to Tuesday with lots of clouds. In fact, one model has Norman remnants moving backward & moving DIRECTLY overhead Tuesday, before shooting off to the east Tuesday night. Brisk east winds pivoting around the old Normal circulation will accompany the clouds & showers. The main steering flow will be way north of here, so the remnants will just sort of wobble around, before stronger jet winds with that approaching cold front push it out.
So, upper ridging is normally a good friend, but it can be an enemy when steering currently are weak. Systems can get cut off & just wobble around, like the Norman remnants.
So, unfortunately, this trend is definitely verified among most model solutions & I will have to put it in the forecast. I hate doing that when it looked so good, so warm & so nice & dry until Friday in last week’s trends.
That said, this reminds me so, so much of last year. Looked like upper ridge with dry, warm weather & an upper low retro-graded or moved backward & brought cool, showery weather in latter September, while the Plains & Canada were VERY WARM. Then, we had a very brief warm-up, before a front came in & cooled it off to the 60s with some patchy frost in early October.
So, we look to have a brief burst of warmth of upper 70s to lower 80s, then front come through to end the week with some t’storms, followed by highs in the upper 50s & lower 60s & lows in the 30s (some places will have a light freeze).