In Brief:
Slightly better storm chances are slated for Thursday before a big western ridge returns us to only small afternoon storm chances.
Forecast Discussion:
One more short wave passes Thursday giving us better storm chances (Figure 1 in the gallery above). The ridge to the west with a high center over NW Arizona is about to grow! The moisture for Thursday is having to travel pretty far from the Gulf to get to us, but it will for one more day (Figure 2). This northwest flow is bringing a bit of haze and smoke in with the moisture (Figure 3) but it isn't very thick this time. Note, severe weather is not expected around Longmont at this time. A nice feature to this pattern is that there is a strong northern component to the air flow into the state, so we won't see abnormally warm temperatures until maybe next week (Figure 4).
Rainfall over the next 48 hours should be quite minimal and confined to the I-25 corridor overall (Figure 5).
The Longer Range Forecast:
In the long term, blobs of moisture will interact with short waves in the northwest flow to give us slightly better storm chances Friday, Sunday and Tuesday afternoons (Figure 4). The eastern plains *might* get a lucky 1/2 inch or more in spots (Figure 6). The longer term forecast is really all about the giant western U.S. ridge that will form and stay in place (Figure 7). Again, that northern flow will keep us from seeing record high tempreatures (whew!).
In Figure 7 you can see the GFS's take on Isaias around Saturday noon. The National Hurricane Center still expectes it to stay below hurricane status (due to the hostile enviroment it is moving through; dry air, wind shear)- but impacts might be felt across Floriday and up the east coast into next week (Figure 8).