The preliminary climate data for both the airport and NWS sites for Grand Forks had everyday of April 2010 with a daily temperature above average.
Were the people who want to believe every cold snap they see or snowstorm somewhere using this April in the Red River Valley to continue to claim there is no global warming or even that there is current global cooling? I actually have no idea because I have not paid so much attention lately to such scientifically ignorant sources. Typically such folks simply shut up when it is warm, but surely some people are still echoing such nonsense.
The point here however is not to say that the every-day-above-average April 2010 in Grand Forks is some sort of proof of global warming. It would maybe be a drop in the filled pool of evidence that establishes the reality of climate change. That is the point. A warm or cold month or a few days of excessive rain, heat, or snow at your house tells you nothing conclusive about long-term global climate trends.
Despite the protests of the denialists and rejectionists the general long-term trend of global warming is well-established. That has been done by strongly supported theory as well as copious amounts of data from decades from across the world. You thinking it has been warm lately where you live is not needed to confirm it, and you thinking it has been cold lately in no way undermines it.
The thing to recognize is that months like April 2010 around Grand Forks are creeping toward being more common and closer to a new and gradually warming "normal". Relatively cold months will still occur (the forecast for the first week of May 2010 looks points to below average temperatures similar to May 2009), they will just not happen as often as relatively warm months. Instead of being evenly split between cool and warm compared to normal, years may average more like 5 cool months and 7 warm months. What we consider notably warm now may be considered simply typical in a couple generations.
Remember, an outdoor thermometer you put up around your home is fine for deciding what to wear any day, but that tool that will neither prove nor overturn the science of climate change.