Updated with new link from Naturescapes
DesertUSA has the following wildflower reports for Northern Arizona:
Bartlett Lake just north of Rattlesnake Cove on the steep slopes west of the road. This was the only area with wildflowers. Other areas at Bartlett that usually have blooms were completely devoid of wildflowers.
Lots of poppys, heliotrope & some lupine on Rainbow Valley trail in Estrella Mt Park
See photos and older reports at: Desert Wildflower reports for Phoenix and Northern Arizona Area – DesertUSA.
Also check out this discussion thread at Naturescape.com: Desert Flower Predictions – Arizona