Presentation PDF (1.0 MB)
Observations show that the gulf surge occurs amid complex synoptic, mesoscale, and convective environments. Preceded by anomalous warming and a low-level nocturnal stable layer, the surge propagates rapidly up the length of the GoC (~17-22 m/s) and is characterized by sharp anomalous cooling and strengthening of the wind in the lowest 2 km of the atmosphere. The surge arrives along the northern GoC during the early morning hours and causes a deepening of the well-mixed boundary layer. Surface pressures rapidly rise as well. Surge characteristics are best observed at sites along the northern GoC and become increasingly difficult to discern farther south.
The weight of the evidence presented in this study suggests that the initial surge over the northern gulf may be due to bore-like disturbances that owed their existence to convective downdrafts impinging on the nocturnal inversion over the region. Following these initial pulses, a deeper layer of sharp cooling and strong winds ensued, which likely represents a Kelvin wave-type disturbance. Another possibility is that the leading edge of this Kelvin wave steepened nonlinearly into a bore-like disturbance. The data are not adequate to delineate between these possible mechanisms.
![](images/flag.png)
![](images/blue_ribbon.png)