Extreme Fire Weather Outlook: 4/5/16

Instead of a New Mexico Weather post this morning, I will post about the Extreme Fire Weather that will affect the northeastern corner of the state today.

The Storm Prediction Center (SPC) has issued an Extreme Fire Weather Outlook today for parts of the western Oklahoma, central Kansas, the Texas Panhandle and northeastern New Mexico.

The SPC is basing this threat on a strong trough passing through the Great Basin which will cause a strong jetstreak to pass through the area. Also, a surface cold front that extends from a surface low pressure system in southeastern Colorado is expected to intensify as it moves northeast. This cold front will cause an abrupt wind shift in the threat area.

Synoptically speaking, the 300 mb NAM chart (from Unisys) shows the trough extending from the Dakotas into Nevada by this afternoon. The jetstreak is not very strong on this NAM, but it will continue to intensify into the late evening.

The 500 mb NAM chart shows some intense Positive Vorticity Advection (PVA) moving in behind the trough. Worst case scenario is that the dry, windy threat area could be ignited by lightning strikes due to the convection that may accompany this PVA.

The 700 mb NAM chart shows the rapidly-rising air over the threat area and beyond. This may prompt a few lightning strikes, provided there is enough moisture for clouds. Either way, there is a lot of moving air in this region.

The 850 mb NAM chart shows that the cold front is most intense across eastern Colorado, where the Cold Air Advection (CAA) is the strongest. Earlier in the day, there is some Warm Air Advection (WAA) with warmer air moving from New Mexico and the Texas Panhandle into Kansas.

The 12Z upper air sounding from Amarillo, TX, is slightly damper than I was expecting, but there is still only 0.31 inches of precipitable water present in the column. No particular layer is especially humid, either. There was a strong thermal inversion near the surface, and so the 0-3 km average lapse rate was low. The low-level shear was 21 kts, and the wind barbs are showing that the winds pick up speed just above the surface.

The RAP shows the surface pressure gradient increasing just west of the threat area over the next six hours. As this gradient tightens and moves east, the threat of wildfires will become more intense as well.

The Fosberg Parameter is expected to increase significantly over the next six hours as well, reaching values over 70 in the northeastern corner of the state, and values over 80 in the Texas Panhandle.

The water vapor satellite imagery shows some damp air aloft, though the trough (and the dry air behind it) is visible over the Great Basin, stretching into the Dakotas.

Overall, I expect that today may have a few wildfires. Strong winds are possible, as are dry surface conditions, and with the PVA, there is even a natural source of ignition possible. Stay Alert!

Thank you for reading my forecast.

The upper air soundings and mesoscale analysis plots are from the Storm Prediction Center website.
The forecasted upper air soundings are from TwisterData.com.
The surface observation and upper level charts are from Unisys Weather.
The satellite data is from NASA – MSFC


About highplainschasing

This blog is about my tales in storm chasing. My name is Seth Price and I am an instrumentation instructor at New Mexico Tech. My amateur radio call sign is N3MRA.
This entry was posted in Fire Weather, Practicing Concepts, Predictions, Satellite Imagery and tagged , , , , , , , . Bookmark the permalink.

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