# Presentation: 095293

## Case Study:  
Ernesto
August–September 2006

- Ernesto
- August–September 2006

**Jared Klein – SUNY - Albany**

## 300 hPa Analyses:  1200 UTC 31 August 2006

**300 hPa Analyses****:  **1200 UTC 31 August 2006

**300 hPa frontogenesis ****[K (100 km)****−****1 ****(3 h)****−****1****],**** ****θ**** ****(K),**** and wind barbs (kt)**

**Jet much farther downstream than with Ivan (2004)**

**1.0°**** GFS**

**Precipitable water (mm), 300 hPa h (dam), wind speed (m s****−****1****), and div (10****−****5**** s****−****1****)**

## 300 hPa Analyses:  1200 UTC 1 September 2006

**300 hPa Analyses****:  **1200 UTC 1 September 2006

**300 hPa frontogenesis ****[K (100 km)****−****1 ****(3 h)****−****1****],**** ****θ**** ****(K),**** and wind barbs (kt)**

**1.0°**** GFS**

**Precipitable water (mm), 300 hPa h (dam), wind speed (m s****−****1****), and div (10****−****5**** s****−****1****)**

## 925 hPa Analyses:  1200 UTC 31 August 2006

**925 hPa Analyses****:  **1200 UTC 31 August 2006

**925 hPa frontogenesis ****[K (100 km)****−****1 ****(3 h)****−****1****],**** ****θ**** ****(K),**** and wind barbs (kt)**

**WSI radar, 925 hPa ****θ****e ****(K)**** and wind barbs (kt)**

**1.0°**** GFS**

## 925 hPa Analyses:  1200 UTC 1 September 2006

**925 hPa Analyses****:  **1200 UTC 1 September 2006

**925 hPa frontogenesis ****[K (100 km)****−****1 ****(3 h)****−****1****],**** ****θ**** ****(K),**** and wind barbs (kt)**

**WSI radar, 925 hPa ****θ****e ****(K)**** and wind barbs (kt)**

**Highest reflectivity near nose of LLJ/****θ****e ****ridge axis**

**Strong frontogenesis along warm frontal zone**

**1.0°**** GFS**

## 925 hPa Q Vector Diagnosis:  0000 UTC 1 September 2006

**Radar at 0000 UTC 1 September 2006**

**Q****n**** div–con bands within coastal boundary as Ernesto nears landfall**

**Strong forcing for descent–ascent associated with Q****n**** and Q****s**** div–con**

**925 hPa Q Vector Diagnosis****:  **0000 UTC 1 September 2006

**Q**

**Q****n**

**Q****s**

**WSI radar**

**Q vectors (10****−****10**** K m****−****1 ****s****−****1 ****beginning at 2.5 ****×**** 10****−****11****), ****θ**** ****(K) contoured in green, and **
**Q div****–****con (10****−****15**** K m****−****2**** s****−****1****) shaded in cool–warm colors**

**1.0°**** GFS**

## 925 hPa Q Vector Diagnosis:  0600 UTC 1 September 2006

**Radar at 0600 UTC 1 September 2006**

**925 hPa Q Vector Diagnosis****:  **0600 UTC 1 September 2006

**Q**

**Q****n**

**Q****s**

**WSI radar**

**Highest reflectivity near strongest QG forcing for ascent**

**Q vectors (10****−****10**** K m****−****1 ****s****−****1 ****beginning at 2.5 ****×**** 10****−****11****), ****θ**** ****(K) contoured in green, and **
**Q div****–****con (10****−****15**** K m****−****2**** s****−****1****) shaded in cool–warm colors**

**1.0°**** GFS**

## 925 hPa Q Vector Diagnosis:  1200 UTC 1 September 2006

**Radar at 1200 UTC 1 September 2006**

**925 hPa Q Vector Diagnosis****:  **1200 UTC 1 September 2006

**Q**

**Q****n**

**Q****s**

**WSI radar**

**Highest reflectivity near strongest QG forcing for ascent**

**Q vectors (10****−****10**** K m****−****1 ****s****−****1 ****beginning at 2.5 ****×**** 10****−****11****), ****θ**** ****(K) contoured in green, and **
**Q div****–****con (10****−****15**** K m****−****2**** s****−****1****) shaded in cool–warm colors**

**1.0°**** GFS**

## Cross Section of Fn Magnitude:  0000 UTC 1 September 2006

**Cross Section of F****n**** Magnitude:  **0000 UTC 1 September 2006

**925–500 hPa layer-avg **
**F****n ****vectors (10****−****10**** K m****−****1 ****s****−****1****),**
**θ**** (K) contoured in green****, and ****F****n**** div–con ****(10****−****15**** K m****−****2**** s****−****1****) shaded in cool****–warm colors**

**Strongest frontogenesis focused near surface**

**1.0°**** GFS**

**F****n**** magnitude [K (100 km)****−****1 ****(3 h)****−****1****] shaded in green****–****blue, RH shaded in orange, ****θ**** ****(K) contoured in gray, wind barbs (m**** ****s****−****1****), and ****ω****<0**** (****μb**** s****−****1****) contoured in red**

## Cross Section of Fn Magnitude:  1200 UTC 1 September 2006

**Cross Section of F****n**** Magnitude:  **1200 UTC 1 September 2006

**925–500 hPa layer-avg **
**F****n ****vectors (10****−****10**** K m****−****1 ****s****−****1****),**
**θ**** (K) contoured in green****, and ****F****n**** div–con ****(10****−****15**** K m****−****2**** s****−****1****) shaded in cool****–warm colors**

**Strongest frontogenesis focused near surface**

**1.0°**** GFS**

**F****n**** magnitude [K (100 km)****−****1 ****(3 h)****−****1****] shaded in green****–****blue, RH shaded in orange, ****θ**** ****(K) contoured in gray, wind barbs (m**** ****s****−****1****), and ****ω****<0**** (****μb**** s****−****1****) contoured in red**

## 6-h precipitation (in) ending at 

**Heaviest 6-h precip along and on cold side of surface boundary**

**6-h precipitation (in) ending at **
**1200 UTC 1 September 2006**

**0600 UTC 1 September 2006**

**NPVU QPE**

**F****n**** vectors (10****−****10**** K m****−****1 ****s****−****1 ****beginning at 1.0 ****×**** 10****−****10****), ****θ**** ****(K) contoured in green, streamlines contoured in black, and F****n**** div****–****con (10****−****14**** K m****−****2**** s****−****1****) shaded in cool–warm colors**

**1200 UTC 1 September 2006**

**~0.6°**** surface data**

## 6-h precipitation (in) ending at 

**Heaviest 6-h precip along and on cold side of surface boundary**

**6-h precipitation (in) ending at **
**1800 UTC 1 September 2006**

**1200 UTC 1 September 2006**

**NPVU QPE**

**F****n**** vectors (10****−****10**** K m****−****1 ****s****−****1 ****beginning at 1.0 ****×**** 10****−****10****), ****θ**** ****(K) contoured in green, streamlines contoured in black, and F****n**** div****–****con (10****−****14**** K m****−****2**** s****−****1****) shaded in cool–warm colors**

**1800 UTC 1 September 2006**

**~0.6°**** surface data**