GFS Ensemble Forecasts - Finally A Bit Of Hope

For the past month we've lived under the 500 mb ridge here in Tucson with mostly clear and dry skies, cold mornings and warm afternoons. Above photo of Catalinas yesterday (Monday, January 20th, MLK Day) afternoon shows the weather highlight of the day as some contrails zipped by.

However, last evening's runs of the GFS ensemble forecasts hold out some hope in the longer term. The three panels below show the 500 mb average heights and anomalies forecast at 84-h, 156-h, and 228-h. The bottom panel is valid at 12 UTC on Thursday, January 30th. The west coast ridge remains extreme through 7 days but then, by the end of the month, a trough from the Pacific plows through the ridge and weakens it dramatically. It's a long way out but we can hope that it's got the trend right.